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Article

Some Properties of the Solution to a System of Quaternion Matrix Equations

1
School of Mathematics, East China University of Science and Technology, Shanghai 200237, China
2
Department of Mathematics, Shanghai University, Shanghai 200444, China
*
Author to whom correspondence should be addressed.
Axioms 2022, 11(12), 710; https://doi.org/10.3390/axioms11120710
Submission received: 13 November 2022 / Revised: 4 December 2022 / Accepted: 6 December 2022 / Published: 8 December 2022
(This article belongs to the Special Issue Advances in Linear Algebra)

Abstract

:
This paper investigates the properties of the ϕ -skew-Hermitian solution to the system of quaternion matrix equations involving ϕ -skew-Hermicity with four unknowns A i X i ( A i ) ϕ + B i X i + 1 ( B i ) ϕ = C i , ( i = 1 , 2 , 3 ) , A 4 X 4 ( A 4 ) ϕ = C 4 . We present the general ϕ -skew-Hermitian solution to this system. Moreover, we derive the β ( ϕ ) -signature bounds of the ϕ -skew-Hermitian solution X 1 in terms of the coefficient matrices. We also give some necessary and sufficient conditions for the system to have β ( ϕ )-positive semidefinite, β ( ϕ )-positive definite, β ( ϕ )-negative semidefinite and β ( ϕ )-negative definite solutions.

1. Introduction

The quaternion matrix can be used in quantum mechanics [1], color image processing (e.g., [2,3,4]), and signal processing [5], etc. Some researchers have studied the solvability conditions and solutions to some quaternion matrix equations (e.g., [6,7,8,9]).
Hermitian solutions to quaternion matrix equations have been discussed in many papers. Rodman investigated the definitions of ϕ -Hermitian, ϕ -skew-Hermitian quaternion matrices (Definition 3.6.1 in [10]) and presented a decomposition of ϕ -skew-Hermitian quaternion matrix (see Lemma 1). Since then, some researchers have considered the applications of ϕ (-skew)-Hermitian quaternion matrices in various aspects. Aghamollaei and Rahjoo [11] established the numerical ranges with respect to nonstandard involutions on quaternionic. Rahjoo et al. [12] studied the numerical ranges with respect to nonstandard involutions. He et al. [13] considered two systems of quaternion matrix equations
A 1 X Y B 1 = C 1 , A 2 Z Y B 2 = C 2 , Z = Z ϕ ,
and
A 1 X Y B 1 = C 1 , A 2 Y Z B 2 = C 2 , Z = Z ϕ .
Wang and Jiang [14] derived the ranks of the skew-Hermitian solution to a classical quaternion matrix equation with two unknowns. The η -Hermitian quaternion matrix decompositions have applications in signal processing and linear modeling (e.g., [15,16,17,18]). Moreover, He [19] has been investigated the structure, properties and applications of a simultaneous decomposition for quaternion matrices involving ϕ -skew-Hermitian. He et al. [20] presented some solvability conditions to a system of quaternion matrix equations involving ϕ -skew-Hermicity
A 1 X 1 ( A 1 ) ϕ + B 1 X 2 ( B 1 ) ϕ = C 1 , A 2 X 2 ( A 2 ) ϕ + B 2 X 3 ( B 2 ) ϕ = C 2 , A 3 X 3 ( A 3 ) ϕ + B 3 X 4 ( B 3 ) ϕ = C 3 , A 4 X 4 ( A 4 ) ϕ = C 4 , X i = ( X i ) ϕ ,
where A i H p i × t i , B i H p i × t i + 1 , C i H p i × p i , and C i are ϕ -skew-Hermitian matrices. As we know, the solution of the system (1) has not been studied. On the other hand, a special case of the system (1)
A 1 X 1 ( A 1 ) ϕ = C 1
can be used in statistics and vibration theory (e.g., [21,22]). The matrix Equation (2) can be used to consider an inverse problem arising in structural modification of the dynamic behaviour (e.g., [23,24]). We conjecture that the main system (1) will also play an important role in the statistics, vibration theory and dynamic behaviour. Inspired by the Hermitian solutions to quaternion matrix equations have widely applications in system and control theory, we consider the expression and properties of the solution to the system (1) in this paper.
The remainder of this paper is organized as follows. In Section 2, we review some definitions and introduce some notations. In Section 3, we provide the general solution to the system (1). In Section 4, we give the β ( ϕ )-signature bounds of the solution X 1 to the system (1) and give some necessary and sufficient conditions for the system (1) to have β ( ϕ )-positive semidefinite, β ( ϕ )-positive definite, β ( ϕ )-negative semidefinite and β ( ϕ )-negative definite solutions.

2. Preliminaries

In this section, we review some definitions.
Let R denote the fields of the real numbers. Let H be a four dimensional vector space over R with an ordered basis 1 , i , j , k [25]. Note that i , j , k satisfies
i 2 = j 2 = k 2 = 1 ,
i j = j i = k , j k = k j = i , k i = i k = j .
A real quaternion simply called quaternion is a vector x = a 0 + a 1 i + a 2 j + a 3 k H with real coefficients a 0 , a 1 , a 2 , a 3 .
The definition of nonstandard involution is giving as follows.
Definition 1
(Non-standard Involution [10]). Let ϕ be an anti-endomorphism of H . Assume that ϕ does not map H into zero. Then, ϕ is one-to-one and onto H . Thus, ϕ is an anti-automorphism. Moreover, ϕ is real linear and can be represented as a 4 × 4 real matrix with respect to the basis { 1 , i , j , k } . Then, ϕ is a non-standard involution if and only if
ϕ = 1 0 0 T ,
where T is a 3 × 3 real orthogonal symmetric matrix with eigenvalues 1 , 1 , 1 .
Rodman [10] considered some properties of nonstandard involution. Next, we review the definition of ϕ -skew-Hermitian.
Definition 2
( ϕ -skew-Hermitian [10]). A H n × n is said to be ϕ-skew-Hermitian if A = ( A ) ϕ , where ϕ is a nonstandard involution.
The canonical form of a ϕ -skew-Hermitian matrix is presented in [10]. First, we review the definition of ϕ -congruent.
Definition 3
( ϕ -congruent [10]). The quaternion matrices A, B H n × n are ϕ-congruent if A = S B S ϕ , where S is an invertible quaternion matrix and ϕ is a nonstandard involution.
Lemma 1
([10]). Let ϕ be a nonstandard involution. For every ϕ-skew-Hermitian matrix A H n × n , there exists an invertible matrix S H n × n such that
S A S ϕ = 0 0 0 0 β I p 0 0 0 β I q , β = β ( ϕ ) ,
where the unit ϕ-skew-Hermitian quaternion β is fixed and denoted by β ( ϕ ) . Moreover, the integers p and q are uniquely determined by A (for a fixed β(ϕ)).
According to Lemma 1, the definition of β ( ϕ ) -signature of a ϕ -skew-Hermitian quaternion matrix A is provided.
Definition 4
( β ( ϕ ) -signature [10]). We say that the ordered triple of nonnegative integers
( ln + ( A ) , ln ( A ) , ln 0 ( A ) ) : = ( p , q , n p q )
is the β ( ϕ ) -signature of a ϕ-skew-Hermitian quaternion matrix A, as in Lemma 1. The matrix A is said to be β ( ϕ ) -positive definite, β ( ϕ ) -positive semidefinite, if ln + ( A ) = n , ln + ( A ) + ln 0 ( A ) = n , respectively. Analogously, β ( ϕ ) -negative definite and β ( ϕ ) -negative semidefinite ϕ-skew-Hermitian quaternion matrices are defined.

3. The General ϕ-Skew-Hermitian Solution to the System (1)

In this section, we provide the general ϕ -skew-Hermitian solution to the system (1).
Using the results of Lemma 1 in [20], there exist nonsingular matrices T i ^ H t i × t i , P i ^ H p i × p i , ( i = 1 , 2 , 3 ) , T ^ 4 H t 4 × t 4 , P ^ 4 H p 4 × p 4 such that
P i ^ A i T i ^ = S a i , P i ^ B i T ^ i + 1 = S b i , P ^ 4 A 4 T ^ 4 = S a 4 .
Therefore, the system (1) is equivalent to the following system:
S a 1 X ^ 1 ( S a 1 ) ϕ + S b 1 X ^ 2 ( S b 1 ) ϕ = D k j ( 1 ) , S a 2 X ^ 2 ( S a 2 ) ϕ + S b 2 X ^ 3 ( S b 2 ) ϕ = D k j ( 2 ) , S a 3 X ^ 3 ( S a 3 ) ϕ + S b 3 X ^ 4 ( S b 3 ) ϕ = D k j ( 3 ) , S a 4 X ^ 4 ( S a 4 ) ϕ = D k j ( 4 ) ,
where X i = ( X i ) ϕ , D k j ( i ) = P ^ i C i ( P ^ i ) ϕ , S a i and S b i have the following form
S a 1 S b 1 S a 2 S b 2 S a 3 S b 3 S a 4 = ( I 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ) .
The above idea and symbols are presented in [20].
In order to give the general ϕ -skew-Hermitian solution to the system (1), we need to obtain the general ϕ -skew-Hermitian solution to the system (4). The following theorem gives the general ϕ -skew-Hermitian solution to the system (1).
Theorem 1.
Assume that the system (1) is consistent. The general ϕ-skew-Hermitian solution to the system (1) can be expressed as
X 1 = T ^ 1 X ^ 1 ( T ^ 1 ) ϕ , X 2 = T ^ 2 X ^ 2 ( T ^ 2 ) ϕ , X 3 = T ^ 3 X ^ 3 ( T ^ 3 ) ϕ , X 4 = T ^ 4 X ^ 4 ( T ^ 4 ) ϕ ,
where
X ^ 1 = D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) ϕ ( D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ) ϕ ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 16 ( 1 ) X 16 ( 2 ) ) ϕ ( D 26 ( 1 ) X 26 ( 2 ) ) ϕ ( D 36 ( 1 ) X 36 ( 2 ) ) ϕ ( D 17 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( X 18 ( 1 ) ) ϕ ( X 28 ( 1 ) ) ϕ ( X 38 ( 1 ) ) ϕ D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 15 ( 1 ) D 15 ( 2 ) D 16 ( 1 ) X 16 ( 2 ) D 17 ( 1 ) X 18 ( 1 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) D 25 ( 1 ) D 25 ( 2 ) D 26 ( 1 ) X 26 ( 2 ) D 27 ( 1 ) X 28 ( 1 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) D 35 ( 1 ) D 35 ( 2 ) D 36 ( 1 ) X 36 ( 2 ) D 37 ( 1 ) X 38 ( 1 ) D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) D 45 ( 1 ) D 45 ( 2 ) D 46 ( 1 ) X 46 ( 2 ) D 47 ( 1 ) X 48 ( 1 ) ( D 45 ( 1 ) D 45 ( 2 ) ) ϕ D 55 ( 1 ) D 55 ( 2 ) D 56 ( 1 ) X 56 ( 2 ) D 57 ( 1 ) X 58 ( 1 ) ( D 46 ( 1 ) X 46 ( 2 ) ) ϕ ( D 56 ( 1 ) X 56 ( 2 ) ) ϕ D 66 ( 1 ) X 66 ( 2 ) D 67 ( 1 ) X 68 ( 1 ) ( D 47 ( 1 ) ) ϕ ( D 57 ( 1 ) ) ϕ ( D 67 ( 1 ) ) ϕ D 77 ( 1 ) X 78 ( 1 ) ( X 48 ( 1 ) ) ϕ ( X 58 ( 1 ) ) ϕ ( X 68 ( 1 ) ) ϕ ( X 78 ( 1 ) ) ϕ X 88 ( 1 ) ,
X ^ 2 = D 11 ( 2 ) D 11 ( 3 ) + D 11 ( 4 ) D 12 ( 2 ) D 12 ( 3 ) + X 12 ( 4 ) D 13 ( 2 ) D 13 ( 3 ) D 14 ( 2 ) X 14 ( 3 ) D 15 ( 2 ) X 16 ( 2 ) ( D 12 ( 2 ) D 12 ( 3 ) + X 12 ( 4 ) ) ϕ D 22 ( 2 ) D 22 ( 3 ) + X 22 ( 4 ) D 23 ( 2 ) D 23 ( 3 ) D 24 ( 2 ) X 24 ( 3 ) D 25 ( 2 ) X 26 ( 2 ) ( D 13 ( 2 ) D 13 ( 3 ) ) ϕ ( D 23 ( 2 ) D 23 ( 3 ) ) ϕ D 33 ( 2 ) D 33 ( 3 ) D 34 ( 2 ) X 34 ( 3 ) D 35 ( 2 ) X 36 ( 2 ) ( D 14 ( 2 ) X 14 ( 3 ) ) ϕ ( D 24 ( 2 ) X 24 ( 3 ) ) ϕ ( D 34 ( 2 ) X 34 ( 3 ) ) ϕ D 44 ( 2 ) X 44 ( 3 ) D 45 ( 2 ) X 46 ( 2 ) ( D 15 ( 2 ) ) ϕ ( D 25 ( 2 ) ) ϕ ( D 35 ( 2 ) ) ϕ ( D 45 ( 2 ) ) ϕ D 55 ( 2 ) X 56 ( 2 ) ( X 16 ( 2 ) ) ϕ ( X 26 ( 2 ) ) ϕ ( X 36 ( 2 ) ) ϕ ( X 46 ( 2 ) ) ϕ ( X 56 ( 2 ) ) ϕ X 66 ( 2 ) ( D 16 ( 2 ) D 14 ( 3 ) + D 12 ( 4 ) ) ϕ ( D 26 ( 2 ) D 24 ( 3 ) + X 23 ( 4 ) ) ϕ ( D 36 ( 2 ) D 34 ( 3 ) ) ϕ ( D 46 ( 2 ) X 45 ( 3 ) ) ϕ ( D 56 ( 2 ) ) ϕ ( D 68 ( 1 ) ) ϕ ( D 17 ( 2 ) D 15 ( 3 ) + X 14 ( 4 ) ) ϕ ( D 27 ( 2 ) D 25 ( 3 ) + X 24 ( 4 ) ) ϕ ( D 37 ( 2 ) D 35 ( 3 ) ) ϕ ( D 47 ( 2 ) X 46 ( 3 ) ) ϕ ( D 57 ( 2 ) ) ϕ ( D 69 ( 1 ) ) ϕ ( D 18 ( 2 ) D 16 ( 3 ) ) ϕ ( D 28 ( 2 ) D 26 ( 3 ) ) ϕ ( D 38 ( 2 ) D 36 ( 3 ) ) ϕ ( D 48 ( 2 ) X 47 ( 3 ) ) ϕ ( D 58 ( 2 ) ) ϕ ( D 6 , 10 ( 1 ) ) ϕ ( D 19 ( 2 ) X 18 ( 3 ) ) ϕ ( D 29 ( 2 ) X 28 ( 3 ) ) ϕ ( D 39 ( 2 ) X 38 ( 3 ) ) ϕ ( D 49 ( 2 ) X 48 ( 3 ) ) ϕ ( D 59 ( 2 ) ) ϕ ( D 6 , 11 ( 1 ) ) ϕ ( D 1 , 10 ( 2 ) ) ϕ ( D 2 , 10 ( 2 ) ) ϕ ( D 3 , 10 ( 2 ) ) ϕ ( D 4 , 10 ( 2 ) ) ϕ ( D 5 , 10 ( 2 ) ) ϕ ( D 6 , 12 ( 1 ) ) ϕ ( D 1 , 13 ( 1 ) ) ϕ ( D 2 , 13 ( 1 ) ) ϕ ( D 3 , 13 ( 1 ) ) ϕ ( D 4 , 13 ( 1 ) ) ϕ ( D 5 , 13 ( 1 ) ) ϕ ( D 6 , 13 ( 1 ) ) ϕ ( D 1 , 11 ( 2 ) D 17 ( 3 ) + D 13 ( 4 ) ) ϕ ( D 2 , 11 ( 2 ) D 27 ( 3 ) + X 25 ( 4 ) ) ϕ ( D 3 , 11 ( 2 ) D 37 ( 3 ) ) ϕ ( D 4 , 11 ( 2 ) X 49 ( 3 ) ) ϕ ( D 5 , 11 ( 2 ) ) ϕ ( X 6 , 13 ( 2 ) ) ϕ ( D 1 , 12 ( 2 ) D 18 ( 3 ) + X 16 ( 4 ) ) ϕ ( D 2 , 12 ( 2 ) D 28 ( 3 ) + X 26 ( 4 ) ) ϕ ( D 3 , 12 ( 2 ) D 38 ( 3 ) ) ϕ ( D 4 , 12 ( 2 ) X 4 , 10 ( 3 ) ) ϕ ( D 5 , 12 ( 2 ) ) ϕ ( X 6 , 14 ( 2 ) ) ϕ ( D 1 , 13 ( 2 ) D 19 ( 3 ) ) ϕ ( D 2 , 13 ( 2 ) D 29 ( 3 ) ) ϕ ( D 3 , 13 ( 2 ) D 39 ( 3 ) ) ϕ ( D 4 , 13 ( 2 ) X 4 , 11 ( 3 ) ) ϕ ( D 5 , 13 ( 2 ) ) ϕ ( X 6 , 15 ( 2 ) ) ϕ ( D 1 , 14 ( 2 ) X 1 , 12 ( 3 ) ) ϕ ( D 2 , 14 ( 2 ) X 2 , 12 ( 3 ) ) ϕ ( D 3 , 14 ( 2 ) X 3 , 12 ( 3 ) ) ϕ ( D 4 , 14 ( 2 ) X 4 , 12 ( 3 ) ) ϕ ( D 5 , 14 ( 2 ) ) ϕ ( X 6 , 16 ( 2 ) ) ϕ ( D 1 , 15 ( 2 ) ) ϕ ( D 2 , 15 ( 2 ) ) ϕ ( D 3 , 15 ( 2 ) ) ϕ ( D 4 , 15 ( 2 ) ) ϕ ( D 5 , 15 ( 2 ) ) ϕ ( X 6 , 17 ( 2 ) ) ϕ ( X 1 , 18 ( 2 ) ) ϕ ( X 2 , 18 ( 2 ) ) ϕ ( X 3 , 18 ( 2 ) ) ϕ ( X 4 , 18 ( 2 ) ) ϕ ( X 5 , 18 ( 2 ) ) ϕ ( X 6 , 18 ( 2 ) ) ϕ D 16 ( 2 ) D 14 ( 3 ) + D 12 ( 4 ) D 17 ( 2 ) D 15 ( 3 ) + X 14 ( 4 ) D 18 ( 2 ) D 16 ( 3 ) D 19 ( 2 ) X 18 ( 3 ) D 1 , 10 ( 2 ) D 1 , 13 ( 1 ) D 26 ( 2 ) D 24 ( 3 ) + X 23 ( 4 ) D 27 ( 2 ) D 25 ( 3 ) + X 24 ( 4 ) D 28 ( 2 ) D 26 ( 3 ) D 29 ( 2 ) X 28 ( 3 ) D 2 , 10 ( 2 ) D 2 , 13 ( 1 ) D 36 ( 2 ) D 34 ( 3 ) D 37 ( 2 ) D 35 ( 3 ) D 38 ( 2 ) D 36 ( 3 ) D 39 ( 2 ) X 38 ( 3 ) D 3 , 10 ( 2 ) D 3 , 13 ( 1 ) D 46 ( 2 ) X 45 ( 3 ) D 47 ( 2 ) X 46 ( 3 ) D 48 ( 2 ) X 47 ( 3 ) D 49 ( 2 ) X 48 ( 3 ) D 4 , 10 ( 2 ) D 4 , 13 ( 1 ) D 56 ( 2 ) D 57 ( 2 ) D 58 ( 2 ) D 59 ( 2 ) D 5 , 10 ( 2 ) D 5 , 13 ( 1 ) D 68 ( 1 ) D 69 ( 1 ) D 6 , 10 ( 1 ) D 6 , 11 ( 1 ) D 6 , 12 ( 1 ) D 6 , 13 ( 1 ) D 66 ( 2 ) D 44 ( 3 ) + D 22 ( 4 ) D 67 ( 2 ) D 45 ( 3 ) + X 34 ( 4 ) D 68 ( 2 ) D 46 ( 3 ) D 69 ( 2 ) X 58 ( 3 ) D 6 , 10 ( 2 ) D 8 , 13 ( 1 ) ( D 67 ( 2 ) D 45 ( 3 ) + X 34 ( 4 ) ) ϕ D 77 ( 2 ) D 55 ( 3 ) + X 44 ( 4 ) D 78 ( 2 ) D 56 ( 3 ) D 79 ( 2 ) X 68 ( 3 ) D 7 , 10 ( 2 ) D 9 , 13 ( 1 ) ( D 68 ( 2 ) D 46 ( 3 ) ) ϕ ( D 78 ( 2 ) D 56 ( 3 ) ) ϕ D 88 ( 2 ) D 66 ( 3 ) D 89 ( 2 ) X 78 ( 3 ) D 8 , 10 ( 2 ) D 10 , 13 ( 1 ) ( D 69 ( 2 ) X 58 ( 3 ) ) ϕ ( D 79 ( 2 ) X 68 ( 3 ) ) ϕ ( D 89 ( 2 ) X 78 ( 3 ) ) ϕ D 99 ( 2 ) X 88 ( 3 ) D 9 , 10 ( 2 ) D 11 , 13 ( 1 ) ( D 6 , 10 ( 2 ) ) ϕ ( D 7 , 10 ( 2 ) ) ϕ ( D 8 , 10 ( 2 ) ) ϕ ( D 9 , 10 ( 2 ) ) ϕ D 10 , 10 ( 2 ) D 12 , 13 ( 1 ) ( D 8 , 13 ( 1 ) ) ϕ ( D 9 , 13 ( 1 ) ) ϕ ( D 10 , 13 ( 1 ) ) ϕ ( D 11 , 13 ( 1 ) ) ϕ ( D 12 , 13 ( 1 ) ) ϕ D 13 , 13 ( 1 ) ( D 6 , 11 ( 2 ) D 47 ( 3 ) + D 23 ( 4 ) ) ϕ ( D 7 , 11 ( 2 ) D 57 ( 3 ) + X 45 ( 4 ) ) ϕ ( D 8 , 11 ( 2 ) X 69 ( 3 ) ) ϕ ( D 9 , 11 ( 2 ) X 89 ( 3 ) ) ϕ ( D 10 , 11 ( 2 ) ) ϕ ( X 12 , 13 ( 2 ) ) ϕ ( D 6 , 12 ( 2 ) D 48 ( 3 ) + X 36 ( 4 ) ) ϕ ( D 7 , 12 ( 2 ) D 58 ( 3 ) + X 46 ( 4 ) ) ϕ ( D 8 , 12 ( 2 ) D 68 ( 3 ) ) ϕ ( D 9 , 12 ( 2 ) X 8 , 10 ( 3 ) ) ϕ ( D 10 , 12 ( 2 ) ) ϕ ( X 12 , 14 ( 2 ) ) ϕ ( D 6 , 13 ( 2 ) D 49 ( 3 ) ) ϕ ( D 7 , 13 ( 2 ) D 59 ( 3 ) ) ϕ ( D 8 , 13 ( 2 ) D 69 ( 3 ) ) ϕ ( D 9 , 13 ( 2 ) X 8 , 11 ( 3 ) ) ϕ ( D 10 , 13 ( 2 ) ) ϕ ( X 12 , 15 ( 2 ) ) ϕ ( D 6 , 14 ( 2 ) X 5 , 12 ( 3 ) ) ϕ ( D 7 , 14 ( 2 ) X 6 , 12 ( 3 ) ) ϕ ( D 8 , 14 ( 2 ) X 7 , 12 ( 3 ) ) ϕ ( D 9 , 14 ( 2 ) X 8 , 12 ( 3 ) ) ϕ ( D 10 , 14 ( 2 ) ) ϕ ( X 12 , 16 ( 2 ) ) ϕ ( D 6 , 15 ( 2 ) ) ϕ ( D 7 , 15 ( 2 ) ) ϕ ( D 8 , 15 ( 2 ) ) ϕ ( D 9 , 15 ( 2 ) ) ϕ ( D 10 , 15 ( 2 ) ) ϕ ( X 12 , 17 ( 2 ) ) ϕ ( X 7 , 18 ( 2 ) ) ϕ ( X 8 , 18 ( 2 ) ) ϕ ( X 9 , 18 ( 2 ) ) ϕ ( X 10 , 18 ( 2 ) ) ϕ ( X 11 , 18 ( 2 ) ) ϕ ( X 12 , 18 ( 2 ) ) ϕ D 1 , 11 ( 2 ) D 17 ( 3 ) + D 13 ( 4 ) D 1 , 12 ( 2 ) D 18 ( 3 ) + X 16 ( 4 ) D 1 , 13 ( 2 ) D 19 ( 3 ) D 1 , 14 ( 2 ) X 1 , 12 ( 3 ) D 1 , 15 ( 2 ) X 1 , 18 ( 2 ) D 2 , 11 ( 2 ) D 27 ( 3 ) + X 25 ( 4 ) D 2 , 12 ( 2 ) D 28 ( 3 ) + X 26 ( 4 ) D 2 , 13 ( 2 ) D 29 ( 3 ) D 2 , 14 ( 2 ) X 2 , 12 ( 3 ) D 2 , 15 ( 2 ) X 2 , 18 ( 2 ) D 3 , 11 ( 2 ) D 37 ( 3 ) D 3 , 12 ( 2 ) D 38 ( 3 ) D 3 , 13 ( 2 ) D 39 ( 3 ) D 3 , 14 ( 2 ) X 3 , 12 ( 3 ) D 3 , 15 ( 2 ) X 3 , 18 ( 2 ) D 4 , 11 ( 2 ) X 49 ( 3 ) D 4 , 12 ( 2 ) X 4 , 10 ( 3 ) D 4 , 13 ( 2 ) X 4 , 11 ( 3 ) D 4 , 14 ( 2 ) X 4 , 12 ( 3 ) D 4 , 15 ( 2 ) X 4 , 18 ( 2 ) D 5 , 11 ( 2 ) D 5 , 12 ( 2 ) D 5 , 13 ( 2 ) D 5 , 14 ( 2 ) D 5 , 15 ( 2 ) X 5 , 18 ( 2 ) X 6 , 13 ( 2 ) X 6 , 14 ( 2 ) X 6 , 15 ( 2 ) X 6 , 16 ( 2 ) X 6 , 17 ( 2 ) X 6 , 18 ( 2 ) D 6 , 11 ( 2 ) D 47 ( 3 ) + D 23 ( 4 ) D 6 , 12 ( 2 ) D 48 ( 3 ) + X 36 ( 4 ) D 6 , 13 ( 2 ) D 49 ( 3 ) D 6 , 14 ( 2 ) X 5 , 12 ( 3 ) D 6 , 15 ( 2 ) X 7 , 18 ( 2 ) D 7 , 11 ( 2 ) D 57 ( 3 ) + X 45 ( 4 ) D 7 , 12 ( 2 ) D 58 ( 3 ) + X 46 ( 4 ) D 7 , 13 ( 2 ) D 59 ( 3 ) D 7 , 14 ( 2 ) X 6 , 12 ( 3 ) D 7 , 15 ( 2 ) X 8 , 18 ( 2 ) D 8 , 11 ( 2 ) D 67 ( 3 ) D 8 , 12 ( 2 ) D 68 ( 3 ) D 8 , 13 ( 2 ) D 69 ( 3 ) D 8 , 14 ( 2 ) X 7 , 12 ( 3 ) D 8 , 15 ( 2 ) X 9 , 18 ( 2 ) D 9 , 11 ( 2 ) X 89 ( 3 ) D 9 , 12 ( 2 ) X 8 , 10 ( 3 ) D 9 , 13 ( 2 ) X 8 , 11 ( 3 ) D 9 , 14 ( 2 ) X 8 , 12 ( 3 ) D 9 , 15 ( 2 ) X 10 , 18 ( 2 ) D 10 , 11 ( 2 ) D 10 , 12 ( 2 ) D 10 , 13 ( 2 ) D 10 , 14 ( 2 ) D 10 , 15 ( 2 ) X 11 , 18 ( 2 ) X 12 , 13 ( 2 ) X 12 , 14 ( 2 ) X 12 , 15 ( 2 ) X 12 , 16 ( 2 ) X 12 , 17 ( 2 ) X 12 , 18 ( 2 ) D 11 , 11 ( 2 ) D 77 ( 3 ) + D 33 ( 4 ) D 11 , 12 ( 2 ) D 78 ( 3 ) + X 56 ( 4 ) D 11 , 13 ( 2 ) D 79 ( 3 ) D 11 , 14 ( 2 ) X 9 , 12 ( 3 ) D 11 , 15 ( 2 ) X 13 , 18 ( 2 ) ( D 11 , 12 ( 2 ) D 78 ( 3 ) + X 56 ( 4 ) ) ϕ D 12 , 12 ( 2 ) D 88 ( 3 ) + X 66 ( 4 ) D 12 , 13 ( 2 ) X 10 , 11 ( 3 ) D 12 , 14 ( 2 ) X 10 , 12 ( 3 ) D 12 , 15 ( 2 ) X 14 , 18 ( 2 ) ( D 11 , 13 ( 2 ) D 79 ( 3 ) ) ϕ ( D 12 , 13 ( 2 ) X 10 , 11 ( 3 ) ) ϕ D 13 , 13 ( 2 ) D 99 ( 3 ) D 13 , 14 ( 2 ) X 11 , 12 ( 3 ) D 13 , 15 ( 2 ) X 15 , 18 ( 2 ) ( D 11 , 14 ( 2 ) X 9 , 12 ( 3 ) ) ϕ ( D 12 , 14 ( 2 ) X 10 , 12 ( 3 ) ) ϕ ( D 13 , 14 ( 2 ) X 11 , 12 ( 3 ) ) ϕ D 14 , 14 ( 2 ) X 12 , 12 ( 3 ) D 14 , 15 ( 2 ) X 16 , 18 ( 2 ) ( D 11 , 15 ( 2 ) ) ϕ ( D 12 , 15 ( 2 ) ) ϕ ( D 13 , 15 ( 2 ) ) ϕ ( D 14 , 15 ( 2 ) ) ϕ D 15 , 15 ( 2 ) X 17 , 18 ( 2 ) ( X 13 , 18 ( 2 ) ) ϕ ( X 14 , 18 ( 2 ) ) ϕ ( X 15 , 18 ( 2 ) ) ϕ ( X 16 , 18 ( 2 ) ) ϕ ( X 17 , 18 ( 2 ) ) ϕ X 18 , 18 ( 2 ) ,
X ^ 3 = D 11 ( 3 ) D 11 ( 4 ) D 12 ( 3 ) X 12 ( 4 ) D 13 ( 3 ) X 14 ( 3 ) D 14 ( 3 ) D 12 ( 4 ) D 15 ( 3 ) X 14 ( 4 ) D 16 ( 3 ) ( D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 22 ( 3 ) X 22 ( 4 ) D 23 ( 3 ) X 24 ( 3 ) D 24 ( 3 ) X 23 ( 4 ) D 25 ( 3 ) X 24 ( 4 ) D 26 ( 3 ) ( D 13 ( 3 ) ) ϕ ( D 23 ( 3 ) ) ϕ D 33 ( 3 ) X 34 ( 3 ) D 34 ( 3 ) D 35 ( 3 ) D 36 ( 3 ) ( X 14 ( 3 ) ) ϕ ( X 24 ( 3 ) ) ϕ ( X 34 ( 3 ) ) ϕ X 44 ( 3 ) X 45 ( 3 ) X 46 ( 3 ) X 47 ( 3 ) ( D 14 ( 3 ) D 12 ( 4 ) ) ϕ ( D 24 ( 3 ) X 23 ( 4 ) ) ϕ ( D 34 ( 3 ) ) ϕ ( X 45 ( 3 ) ) ϕ D 44 ( 3 ) D 22 ( 4 ) D 45 ( 3 ) X 34 ( 4 ) D 46 ( 3 ) ( D 15 ( 3 ) X 14 ( 4 ) ) ϕ ( D 25 ( 3 ) X 24 ( 4 ) ) ϕ ( D 35 ( 3 ) ) ϕ ( X 46 ( 3 ) ) ϕ ( D 45 ( 3 ) X 34 ( 4 ) ) ϕ D 55 ( 3 ) X 44 ( 4 ) D 56 ( 3 ) ( D 16 ( 3 ) ) ϕ ( D 26 ( 3 ) ) ϕ ( D 36 ( 3 ) ) ϕ ( X 47 ( 3 ) ) ϕ ( D 46 ( 3 ) ) ϕ ( D 56 ( 3 ) ) ϕ D 66 ( 3 ) ( X 18 ( 3 ) ) ϕ ( X 28 ( 3 ) ) ϕ ( X 38 ( 3 ) ) ϕ ( X 48 ( 3 ) ) ϕ ( X 58 ( 3 ) ) ϕ ( X 68 ( 3 ) ) ϕ ( X 78 ( 3 ) ) ϕ ( D 17 ( 3 ) D 13 ( 4 ) ) ϕ ( D 27 ( 3 ) X 25 ( 4 ) ) ϕ ( D 37 ( 3 ) ) ϕ ( X 49 ( 3 ) ) ϕ ( D 47 ( 3 ) D 23 ( 4 ) ) ϕ ( D 57 ( 3 ) X 45 ( 4 ) ) ϕ ( D 67 ( 3 ) ) ϕ ( D 18 ( 3 ) X 16 ( 4 ) ) ϕ ( D 28 ( 3 ) X 26 ( 4 ) ) ϕ ( D 38 ( 3 ) ) ϕ ( X 4 , 10 ( 3 ) ) ϕ ( D 48 ( 3 ) X 36 ( 4 ) ) ϕ ( D 58 ( 3 ) X 46 ( 4 ) ) ϕ ( D 68 ( 3 ) ) ϕ ( D 19 ( 3 ) ) ϕ ( D 29 ( 3 ) ) ϕ ( D 39 ( 3 ) ) ϕ ( X 4 , 11 ( 3 ) ) ϕ ( D 49 ( 3 ) ) ϕ ( D 59 ( 3 ) ) ϕ ( D 69 ( 3 ) ) ϕ ( X 1 , 12 ( 3 ) ) ϕ ( X 2 , 12 ( 3 ) ) ϕ ( X 3 , 12 ( 3 ) ) ϕ ( X 4 , 12 ( 3 ) ) ϕ ( X 5 , 12 ( 3 ) ) ϕ ( X 6 , 12 ( 3 ) ) ϕ ( X 7 , 12 ( 3 ) ) ϕ ( D 1 , 10 ( 3 ) D 14 ( 4 ) ) ϕ ( D 2 , 10 ( 3 ) X 27 ( 4 ) ) ϕ ( D 3 , 10 ( 3 ) ) ϕ ( D 4 , 16 ( 2 ) ) ϕ ( D 4 , 10 ( 3 ) D 24 ( 4 ) ) ϕ ( D 5 , 10 ( 3 ) X 47 ( 4 ) ) ϕ ( D 6 , 10 ( 3 ) ) ϕ ( D 1 , 11 ( 3 ) X 18 ( 4 ) ) ϕ ( D 2 , 11 ( 3 ) X 28 ( 4 ) ) ϕ ( D 3 , 11 ( 3 ) ) ϕ ( D 4 , 17 ( 2 ) ) ϕ ( D 4 , 11 ( 3 ) X 38 ( 4 ) ) ϕ ( D 5 , 11 ( 3 ) X 48 ( 4 ) ) ϕ ( D 6 , 11 ( 3 ) ) ϕ ( D 1 , 12 ( 3 ) ) ϕ ( D 2 , 12 ( 3 ) ) ϕ ( D 3 , 12 ( 3 ) ) ϕ ( D 4 , 18 ( 2 ) ) ϕ ( D 4 , 12 ( 3 ) ) ϕ ( D 5 , 12 ( 3 ) ) ϕ ( D 6 , 12 ( 3 ) ) ϕ ( D 1 , 19 ( 2 ) ) ϕ ( D 2 , 19 ( 2 ) ) ϕ ( D 3 , 19 ( 2 ) ) ϕ ( D 4 , 19 ( 2 ) ) ϕ ( D 6 , 19 ( 2 ) ) ϕ ( D 7 , 19 ( 2 ) ) ϕ ( D 8 , 19 ( 2 ) ) ϕ ( D 1 , 13 ( 3 ) D 15 ( 4 ) ) ϕ ( D 2 , 13 ( 3 ) X 29 ( 4 ) ) ϕ ( D 3 , 13 ( 3 ) ) ϕ ( X 4 , 17 ( 3 ) ) ϕ ( D 4 , 13 ( 3 ) D 25 ( 4 ) ) ϕ ( D 5 , 13 ( 3 ) X 49 ( 4 ) ) ϕ ( D 6 , 13 ( 3 ) ) ϕ ( D 1 , 14 ( 3 ) X 1 , 10 ( 4 ) ) ϕ ( D 2 , 14 ( 3 ) X 2 , 10 ( 4 ) ) ϕ ( D 3 , 14 ( 3 ) ) ϕ ( X 4 , 18 ( 3 ) ) ϕ ( D 4 , 14 ( 3 ) X 3 , 10 ( 4 ) ) ϕ ( D 5 , 14 ( 3 ) X 4 , 10 ( 4 ) ) ϕ ( D 6 , 14 ( 3 ) ) ϕ ( D 1 , 15 ( 3 ) ) ϕ ( D 2 , 15 ( 3 ) ) ϕ ( D 3 , 15 ( 3 ) ) ϕ ( X 4 , 19 ( 3 ) ) ϕ ( D 4 , 15 ( 3 ) ) ϕ ( D 5 , 15 ( 3 ) ) ϕ ( D 6 , 15 ( 3 ) ) ϕ ( X 1 , 20 ( 3 ) ) ϕ ( X 2 , 20 ( 3 ) ) ϕ ( X 3 , 20 ( 3 ) ) ϕ ( X 4 , 20 ( 3 ) ) ϕ ( X 5 , 20 ( 3 ) ) ϕ ( X 6 , 20 ( 3 ) ) ϕ ( X 7 , 20 ( 3 ) ) ϕ X 18 ( 3 ) D 17 ( 3 ) D 13 ( 4 ) D 18 ( 3 ) X 16 ( 4 ) D 19 ( 3 ) X 1 , 12 ( 3 ) D 1 , 10 ( 3 ) D 14 ( 4 ) D 1 , 11 ( 3 ) X 18 ( 4 ) X 28 ( 3 ) D 27 ( 3 ) X 25 ( 4 ) D 28 ( 3 ) X 26 ( 4 ) D 29 ( 3 ) X 2 , 12 ( 3 ) D 2 , 10 ( 3 ) X 27 ( 4 ) D 2 , 11 ( 3 ) X 28 ( 4 ) X 38 ( 3 ) D 37 ( 3 ) D 38 ( 3 ) D 39 ( 3 ) X 3 , 12 ( 3 ) D 3 , 10 ( 3 ) D 3 , 11 ( 3 ) X 48 ( 3 ) X 49 ( 3 ) X 4 , 10 ( 3 ) X 4 , 11 ( 3 ) X 4 , 12 ( 3 ) D 4 , 16 ( 2 ) D 4 , 17 ( 2 ) X 58 ( 3 ) D 47 ( 3 ) D 23 ( 4 ) D 48 ( 3 ) X 36 ( 4 ) D 49 ( 3 ) X 5 , 12 ( 3 ) D 4 , 10 ( 3 ) D 24 ( 4 ) D 4 , 11 ( 3 ) X 38 ( 4 ) X 68 ( 3 ) D 57 ( 3 ) X 45 ( 4 ) D 58 ( 3 ) X 46 ( 4 ) D 59 ( 3 ) X 6 , 12 ( 3 ) D 5 , 10 ( 3 ) X 47 ( 4 ) D 5 , 11 ( 3 ) X 48 ( 4 ) X 78 ( 3 ) D 67 ( 3 ) D 68 ( 3 ) D 69 ( 3 ) X 7 , 12 ( 3 ) D 6 , 10 ( 3 ) D 6 , 11 ( 3 ) X 88 ( 3 ) X 89 ( 3 ) X 8 , 10 ( 3 ) X 8 , 11 ( 3 ) X 8 , 12 ( 3 ) D 9 , 16 ( 2 ) D 9 , 17 ( 2 ) ( X 89 ( 3 ) ) ϕ D 77 ( 3 ) D 33 ( 4 ) D 78 ( 3 ) X 56 ( 4 ) D 79 ( 3 ) X 9 , 12 ( 3 ) D 7 , 10 ( 3 ) D 34 ( 4 ) D 7 , 11 ( 3 ) X 58 ( 4 ) ( X 8 , 10 ( 3 ) ) ϕ ( D 78 ( 3 ) X 56 ( 4 ) ) ϕ D 88 ( 3 ) X 66 ( 4 ) D 89 ( 3 ) X 10 , 12 ( 3 ) D 8 , 10 ( 3 ) X 67 ( 4 ) D 8 , 11 ( 3 ) X 68 ( 4 ) ( X 8 , 11 ( 3 ) ) ϕ ( D 79 ( 3 ) ) ϕ ( D 89 ( 3 ) ) ϕ D 99 ( 3 ) X 11 , 12 ( 3 ) D 9 , 10 ( 3 ) D 9 , 11 ( 3 ) ( X 8 , 12 ( 3 ) ) ϕ ( X 9 , 12 ( 3 ) ) ϕ ( X 10 , 12 ( 3 ) ) ϕ ( X 11 , 12 ( 3 ) ) ϕ X 12 , 12 ( 3 ) D 14 , 16 ( 2 ) D 14 , 17 ( 2 ) ( D 9 , 16 ( 2 ) ) ϕ ( D 7 , 10 ( 3 ) D 34 ( 4 ) ) ϕ ( D 8 , 10 ( 3 ) X 67 ( 4 ) ) ϕ ( D 9 , 10 ( 3 ) ) ϕ ( D 14 , 16 ( 2 ) ) ϕ D 10 , 10 ( 3 ) D 44 ( 4 ) D 10 , 11 ( 3 ) X 78 ( 4 ) ( D 9 , 17 ( 2 ) ) ϕ ( D 7 , 11 ( 3 ) X 58 ( 4 ) ) ϕ ( D 8 , 11 ( 3 ) X 68 ( 4 ) ) ϕ ( D 9 , 11 ( 3 ) ) ϕ ( D 14 , 17 ( 2 ) ) ϕ ( D 10 , 11 ( 3 ) X 78 ( 4 ) ) ϕ D 11 , 11 ( 3 ) X 88 ( 4 ) ( D 9 , 18 ( 2 ) ) ϕ ( D 7 , 12 ( 3 ) ) ϕ ( D 8 , 12 ( 3 ) ) ϕ ( D 9 , 12 ( 3 ) ) ϕ ( D 14 , 18 ( 2 ) ) ϕ ( D 10 , 12 ( 3 ) ) ϕ ( D 11 , 12 ( 3 ) ) ϕ ( D 9 , 19 ( 2 ) ) ϕ ( D 11 , 19 ( 2 ) ) ϕ ( D 12 , 19 ( 2 ) ) ϕ ( D 13 , 19 ( 2 ) ) ϕ ( D 14 , 19 ( 2 ) ) ϕ ( D 16 , 19 ( 2 ) ) ϕ ( D 17 , 19 ( 2 ) ) ϕ ( X 8 , 17 ( 3 ) ) ϕ ( D 7 , 13 ( 3 ) D 35 ( 4 ) ) ϕ ( D 8 , 13 ( 3 ) X 69 ( 4 ) ) ϕ ( D 9 , 13 ( 3 ) ) ϕ ( X 12 , 17 ( 3 ) ) ϕ ( D 10 , 13 ( 3 ) D 45 ( 4 ) ) ϕ ( D 11 , 13 ( 3 ) X 89 ( 4 ) ) ϕ ( X 8 , 18 ( 3 ) ) ϕ ( D 7 , 14 ( 3 ) X 5 , 10 ( 4 ) ) ϕ ( D 8 , 14 ( 3 ) X 6 , 10 ( 4 ) ) ϕ ( D 9 , 14 ( 3 ) ) ϕ ( X 12 , 18 ( 3 ) ) ϕ ( D 10 , 14 ( 3 ) X 7 , 10 ( 4 ) ) ϕ ( D 11 , 14 ( 3 ) X 8 , 10 ( 4 ) ) ϕ ( X 8 , 19 ( 3 ) ) ϕ ( D 7 , 15 ( 3 ) ) ϕ ( D 8 , 15 ( 3 ) ) ϕ ( D 9 , 15 ( 3 ) ) ϕ ( X 12 , 19 ( 3 ) ) ϕ ( D 10 , 15 ( 3 ) ) ϕ ( D 11 , 15 ( 3 ) ) ϕ ( X 8 , 20 ( 3 ) ) ϕ ( X 9 , 20 ( 3 ) ) ϕ ( X 10 , 20 ( 3 ) ) ϕ ( X 11 , 20 ( 3 ) ) ϕ ( X 12 , 20 ( 3 ) ) ϕ ( X 13 , 20 ( 3 ) ) ϕ ( X 14 , 20 ( 3 ) ) ϕ D 1 , 12 ( 3 ) D 1 , 19 ( 2 ) D 1 , 13 ( 3 ) D 15 ( 4 ) D 1 , 14 ( 3 ) X 1 , 10 ( 4 ) D 1 , 15 ( 3 ) X 1 , 20 ( 3 ) D 2 , 12 ( 3 ) D 2 , 19 ( 2 ) D 2 , 13 ( 3 ) X 29 ( 4 ) D 2 , 14 ( 3 ) X 2 , 10 ( 4 ) D 2 , 15 ( 3 ) X 2 , 20 ( 3 ) D 3 , 12 ( 3 ) D 3 , 19 ( 2 ) D 3 , 13 ( 3 ) D 3 , 14 ( 3 ) D 3 , 15 ( 3 ) X 3 , 20 ( 3 ) D 4 , 18 ( 2 ) D 4 , 19 ( 2 ) X 4 , 17 ( 3 ) X 4 , 18 ( 3 ) X 4 , 19 ( 3 ) X 4 , 20 ( 3 ) D 4 , 12 ( 3 ) D 6 , 19 ( 2 ) D 4 , 13 ( 3 ) D 25 ( 4 ) D 4 , 14 ( 3 ) X 3 , 10 ( 4 ) D 4 , 15 ( 3 ) X 5 , 20 ( 3 ) D 5 , 12 ( 3 ) D 7 , 19 ( 2 ) D 5 , 13 ( 3 ) X 49 ( 4 ) D 5 , 14 ( 3 ) X 4 , 10 ( 4 ) D 5 , 15 ( 3 ) X 6 , 20 ( 3 ) D 6 , 12 ( 3 ) D 8 , 19 ( 2 ) D 6 , 13 ( 3 ) D 6 , 14 ( 3 ) D 6 , 15 ( 3 ) X 7 , 20 ( 3 ) D 9 , 18 ( 2 ) D 9 , 19 ( 2 ) X 8 , 17 ( 3 ) X 8 , 18 ( 3 ) X 8 , 19 ( 3 ) X 8 , 20 ( 3 ) D 7 , 12 ( 3 ) D 11 , 19 ( 2 ) D 7 , 13 ( 3 ) D 35 ( 4 ) D 7 , 14 ( 3 ) X 5 , 10 ( 4 ) D 7 , 15 ( 3 ) X 9 , 20 ( 3 ) D 8 , 12 ( 3 ) D 12 , 19 ( 2 ) D 8 , 13 ( 3 ) X 69 ( 4 ) D 8 , 14 ( 3 ) X 6 , 10 ( 4 ) D 8 , 15 ( 3 ) X 10 , 20 ( 3 ) D 9 , 12 ( 3 ) D 13 , 19 ( 2 ) D 9 , 13 ( 3 ) D 9 , 14 ( 3 ) D 9 , 15 ( 3 ) X 11 , 20 ( 3 ) D 14 , 18 ( 2 ) D 14 , 19 ( 2 ) X 12 , 17 ( 3 ) X 12 , 18 ( 3 ) X 12 , 19 ( 3 ) X 12 , 20 ( 3 ) D 10 , 12 ( 3 ) D 16 , 19 ( 2 ) D 10 , 13 ( 3 ) D 45 ( 4 ) D 10 , 14 ( 3 ) X 7 , 10 ( 4 ) D 10 , 15 ( 3 ) X 13 , 20 ( 3 ) D 11 , 12 ( 3 ) D 17 , 19 ( 2 ) D 11 , 13 ( 3 ) X 89 ( 4 ) D 11 , 14 ( 3 ) X 8 , 10 ( 4 ) D 11 , 15 ( 3 ) X 14 , 20 ( 3 ) D 12 , 12 ( 3 ) D 18 , 19 ( 2 ) D 12 , 13 ( 3 ) D 12 , 14 ( 3 ) D 12 , 15 ( 3 ) X 15 , 20 ( 3 ) ( D 18 , 19 ( 2 ) ) ϕ D 19 , 19 ( 2 ) X 16 , 17 ( 3 ) X 16 , 18 ( 3 ) X 16 , 19 ( 3 ) X 16 , 20 ( 3 ) ( D 12 , 13 ( 3 ) ) ϕ ( X 16 , 17 ( 3 ) ) ϕ D 13 , 13 ( 3 ) D 55 ( 4 ) D 13 , 14 ( 3 ) X 9 , 10 ( 4 ) D 13 , 15 ( 3 ) X 17 , 20 ( 3 ) ( D 12 , 14 ( 3 ) ) ϕ ( X 16 , 18 ( 3 ) ) ϕ ( D 13 , 14 ( 3 ) X 9 , 10 ( 4 ) ) ϕ D 14 , 14 ( 3 ) X 10 , 10 ( 4 ) D 14 , 15 ( 3 ) X 18 , 20 ( 3 ) ( D 12 , 15 ( 3 ) ) ϕ ( X 16 , 19 ( 3 ) ) ϕ ( D 13 , 15 ( 3 ) ) ϕ ( D 14 , 15 ( 3 ) ) ϕ D 15 , 15 ( 3 ) X 19 , 20 ( 3 ) ( X 15 , 20 ( 3 ) ) ϕ ( X 16 , 20 ( 3 ) ) ϕ ( X 17 , 20 ( 3 ) ) ϕ ( X 18 , 20 ( 3 ) ) ϕ ( X 19 , 20 ( 3 ) ) ϕ X 20 , 20 ( 3 ) ,
X ^ 4 = D 11 ( 4 ) X 12 ( 4 ) D 12 ( 4 ) X 14 ( 4 ) D 13 ( 4 ) X 16 ( 4 ) D 14 ( 4 ) ( X 12 ( 4 ) ) ϕ X 22 ( 4 ) X 23 ( 4 ) X 24 ( 4 ) X 25 ( 4 ) X 26 ( 4 ) X 27 ( 4 ) ( D 12 ( 4 ) ) ϕ ( X 23 ( 4 ) ) ϕ D 22 ( 4 ) X 34 ( 4 ) D 23 ( 4 ) X 36 ( 4 ) D 24 ( 4 ) ( X 14 ( 4 ) ) ϕ ( X 24 ( 4 ) ) ϕ ( X 34 ( 4 ) ) ϕ X 44 ( 4 ) X 45 ( 4 ) X 46 ( 4 ) X 47 ( 4 ) ( D 13 ( 4 ) ) ϕ ( X 25 ( 4 ) ) ϕ ( D 23 ( 4 ) ) ϕ ( X 45 ( 4 ) ) ϕ D 33 ( 4 ) X 56 ( 4 ) D 34 ( 4 ) ( X 16 ( 4 ) ) ϕ ( X 26 ( 4 ) ) ϕ ( X 36 ( 4 ) ) ϕ ( X 46 ( 4 ) ) ϕ ( X 56 ( 4 ) ) ϕ X 66 ( 4 ) X 67 ( 4 ) ( D 14 ( 4 ) ) ϕ ( X 27 ( 4 ) ) ϕ ( D 24 ( 4 ) ) ϕ ( X 47 ( 4 ) ) ϕ ( D 34 ( 4 ) ) ϕ ( X 67 ( 4 ) ) ϕ D 44 ( 4 ) ( X 18 ( 4 ) ) ϕ ( X 28 ( 4 ) ) ϕ ( X 38 ( 4 ) ) ϕ ( X 48 ( 4 ) ) ϕ ( X 58 ( 4 ) ) ϕ ( X 68 ( 4 ) ) ϕ ( X 78 ( 4 ) ) ϕ ( D 15 ( 4 ) ) ϕ ( X 29 ( 4 ) ) ϕ ( D 25 ( 4 ) ) ϕ ( X 49 ( 4 ) ) ϕ ( D 35 ( 4 ) ) ϕ ( X 69 ( 4 ) ) ϕ ( D 45 ( 4 ) ) ϕ ( X 1 , 10 ( 4 ) ) ϕ ( X 2 , 10 ( 4 ) ) ϕ ( X 3 , 10 ( 4 ) ) ϕ ( X 4 , 10 ( 4 ) ) ϕ ( X 5 , 10 ( 4 ) ) ϕ ( X 6 , 10 ( 4 ) ) ϕ ( X 7 , 10 ( 4 ) ) ϕ ( D 16 ( 4 ) ) ϕ ( D 2 , 16 ( 3 ) ) ϕ ( D 26 ( 4 ) ) ϕ ( D 5 , 16 ( 3 ) ) ϕ ( D 36 ( 4 ) ) ϕ ( D 8 , 16 ( 3 ) ) ϕ ( D 46 ( 4 ) ) ϕ ( D 1 , 17 ( 3 ) ) ϕ ( D 2 , 17 ( 3 ) ) ϕ ( D 4 , 17 ( 3 ) ) ϕ ( D 5 , 17 ( 3 ) ) ϕ ( D 7 , 17 ( 3 ) ) ϕ ( D 8 , 17 ( 3 ) ) ϕ ( D 10 , 17 ( 3 ) ) ϕ ( D 17 ( 4 ) ) ϕ ( X 2 , 13 ( 4 ) ) ϕ ( D 27 ( 4 ) ) ϕ ( X 4 , 13 ( 4 ) ) ϕ ( D 37 ( 4 ) ) ϕ ( X 6 , 13 ( 4 ) ) ϕ ( D 47 ( 4 ) ) ϕ ( X 1 , 14 ( 4 ) ) ϕ ( X 2 , 14 ( 4 ) ) ϕ ( X 3 , 14 ( 4 ) ) ϕ ( X 4 , 14 ( 4 ) ) ϕ ( X 5 , 14 ( 4 ) ) ϕ ( X 6 , 14 ( 4 ) ) ϕ ( X 7 , 14 ( 4 ) ) ϕ X 18 ( 4 ) D 15 ( 4 ) X 1 , 10 ( 4 ) D 16 ( 4 ) D 1 , 17 ( 3 ) D 17 ( 4 ) X 1 , 14 ( 4 ) X 28 ( 4 ) X 29 ( 4 ) X 2 , 10 ( 4 ) D 2 , 16 ( 3 ) D 2 , 17 ( 3 ) X 2 , 13 ( 4 ) X 2 , 14 ( 4 ) X 38 ( 4 ) D 25 ( 4 ) X 3 , 10 ( 4 ) D 26 ( 4 ) D 4 , 17 ( 3 ) D 27 ( 4 ) X 3 , 14 ( 4 ) X 48 ( 4 ) X 49 ( 4 ) X 4 , 10 ( 4 ) D 5 , 16 ( 3 ) D 5 , 17 ( 3 ) X 4 , 13 ( 4 ) X 4 , 14 ( 4 ) X 58 ( 4 ) D 35 ( 4 ) X 5 , 10 ( 4 ) D 36 ( 4 ) D 7 , 17 ( 3 ) D 37 ( 4 ) X 5 , 14 ( 4 ) X 68 ( 4 ) X 69 ( 4 ) X 6 , 10 ( 4 ) D 8 , 16 ( 3 ) D 8 , 17 ( 3 ) X 6 , 13 ( 4 ) X 6 , 14 ( 4 ) X 78 ( 4 ) D 45 ( 4 ) X 7 , 10 ( 4 ) D 46 ( 4 ) D 10 , 17 ( 3 ) D 47 ( 4 ) X 7 , 14 ( 4 ) X 88 ( 4 ) X 89 ( 4 ) X 8 , 10 ( 4 ) D 11 , 16 ( 3 ) D 11 , 17 ( 3 ) X 8 , 13 ( 4 ) X 8 , 14 ( 4 ) ( X 89 ( 4 ) ) ϕ D 55 ( 4 ) X 9 , 10 ( 4 ) D 56 ( 4 ) D 13 , 17 ( 3 ) D 57 ( 4 ) X 9 , 14 ( 4 ) ( X 8 , 10 ( 4 ) ) ϕ ( X 9 , 10 ( 4 ) ) ϕ X 10 , 10 ( 4 ) D 14 , 16 ( 3 ) D 14 , 17 ( 3 ) X 10 , 13 ( 4 ) X 10 , 14 ( 4 ) ( D 11 , 16 ( 3 ) ) ϕ ( D 56 ( 4 ) ) ϕ ( D 14 , 16 ( 3 ) ) ϕ D 66 ( 4 ) D 16 , 17 ( 3 ) D 67 ( 4 ) X 11 , 14 ( 4 ) ( D 11 , 17 ( 3 ) ) ϕ ( D 13 , 17 ( 3 ) ) ϕ ( D 14 , 17 ( 3 ) ) ϕ ( D 16 , 17 ( 3 ) ) ϕ D 17 , 17 ( 3 ) X 12 , 13 ( 4 ) X 12 , 14 ( 4 ) ( X 8 , 13 ( 4 ) ) ϕ ( D 57 ( 4 ) ) ϕ ( X 10 , 13 ( 4 ) ) ϕ ( D 67 ( 4 ) ) ϕ ( X 12 , 13 ( 4 ) ) ϕ D 77 ( 4 ) X 13 , 14 ( 4 ) ( X 8 , 14 ( 4 ) ) ϕ ( X 9 , 14 ( 4 ) ) ϕ ( X 10 , 14 ( 4 ) ) ϕ ( X 11 , 14 ( 4 ) ) ϕ ( X 12 , 14 ( 4 ) ) ϕ ( X 13 , 14 ( 4 ) ) ϕ X 14 , 14 ( 4 ) ,
where D k j ( i ) = P ^ i C i ( P ^ i ) ϕ , ( i = 1 , 2 , 3 , 4 ) are defined in [20], and the remaining X l 1 m 1 ( 1 ) , X l 2 m 2 ( 2 ) , X l 3 m 3 ( 3 ) , X l 4 m 4 ( 4 ) are arbitrary matrices over H with appropriate sizes.
Proof. 
According to the idea of [20], we assume X ^ 1 , X ^ 2 , X ^ 3 , X ^ 4 have the following form:
X ^ 1 = ( X ^ 1 ) ϕ = X 11 ( 1 ) X 12 ( 1 ) X 18 ( 1 ) ( X 12 ( 1 ) ) ϕ X 22 ( 1 ) X 28 ( 1 ) ( X 18 ( 1 ) ) ϕ ( X 28 ( 1 ) ) ϕ X 88 ( 1 ) ,
X ^ 2 = ( X ^ 2 ) ϕ = X 11 ( 2 ) X 12 ( 2 ) X 1 , 18 ( 2 ) ( X 12 ( 2 ) ) ϕ X 22 ( 2 ) X 2 , 18 ( 2 ) ( X 1 , 18 ( 2 ) ) ϕ ( X 2 , 18 ( 2 ) ) ϕ X 18 , 18 ( 2 ) ,
X ^ 3 = ( X ^ 3 ) ϕ = X 11 ( 3 ) X 12 ( 3 ) X 1 , 20 ( 3 ) ( X 12 ( 3 ) ) ϕ X 22 ( 3 ) X 2 , 20 ( 3 ) ( X 1 , 20 ( 3 ) ) ϕ ( X 2 , 20 ( 3 ) ) ϕ X 20 , 20 ( 3 ) ,
X ^ 4 = ( X ^ 4 ) ϕ = X 11 ( 4 ) X 12 ( 4 ) X 1 , 14 ( 4 ) ( X 12 ( 4 ) ) ϕ X 22 ( 4 ) X 2 , 14 ( 4 ) ( X 1 , 14 ( 4 ) ) ϕ ( X 2 , 14 ( 4 ) ) ϕ X 14 , 14 ( 4 ) .
Putting X ^ 1 , X ^ 2 , X ^ 3 , X ^ 4 into the Equation (4) yields
( D i j ( 1 ) ) 14 × 14 = ( D 1 ( 1 ) , D 2 ( 1 ) ) ,
( D i j ( 2 ) ) 20 × 20 = ( D 1 ( 2 ) , D 2 ( 2 ) , D 3 ( 2 ) ) ,
( D i j ( 3 ) ) 18 × 18 = ( D 1 ( 3 ) , D 2 ( 3 ) , D 3 ( 3 ) ) ,
( D i j ( 4 ) ) 8 × 8 = X 11 ( 4 ) X 13 ( 4 ) X 15 ( 4 ) X 17 ( 4 ) X 19 ( 4 ) X 1 , 11 ( 4 ) X 1 , 13 ( 4 ) 0 ( X 13 ( 4 ) ) ϕ X 33 ( 4 ) X 35 ( 4 ) X 37 ( 4 ) X 39 ( 4 ) X 3 , 11 ( 4 ) X 3 , 13 ( 4 ) 0 ( X 15 ( 4 ) ) ϕ ( X 35 ( 4 ) ) ϕ X 55 ( 4 ) X 57 ( 4 ) X 59 ( 4 ) X 5 , 11 ( 4 ) X 5 , 13 ( 4 ) 0 ( X 17 ( 4 ) ) ϕ ( X 37 ( 4 ) ) ϕ ( X 57 ( 4 ) ) ϕ X 77 ( 4 ) X 79 ( 4 ) X 7 , 11 ( 4 ) X 7 , 13 ( 4 ) 0 ( X 19 ( 4 ) ) ϕ ( X 39 ( 4 ) ) ϕ ( X 59 ( 4 ) ) ϕ ( X 79 ( 4 ) ) ϕ X 99 ( 4 ) X 9 , 11 ( 4 ) X 9 , 13 ( 4 ) 0 ( X 1 , 11 ( 4 ) ) ϕ ( X 3 , 11 ( 4 ) ) ϕ ( X 5 , 11 ( 4 ) ) ϕ ( X 7 , 11 ( 4 ) ) ϕ ( X 9 , 11 ( 4 ) ) ϕ X 11 , 11 ( 4 ) X 11 , 13 ( 4 ) 0 ( X 1 , 13 ( 4 ) ) ϕ ( X 3 , 13 ( 4 ) ) ϕ ( X 5 , 13 ( 4 ) ) ϕ ( X 7 , 13 ( 4 ) ) ϕ ( X 9 , 13 ( 4 ) ) ϕ ( X 11 , 13 ( 4 ) ) ϕ X 13 , 13 ( 4 ) 0 0 0 0 0 0 0 0 0 ,
where
D 1 ( 1 ) = X 11 ( 1 ) + X 11 ( 2 ) X 12 ( 1 ) + X 12 ( 2 ) X 13 ( 1 ) + X 13 ( 2 ) X 14 ( 1 ) + X 14 ( 2 ) X 15 ( 1 ) + X 15 ( 2 ) ( X 12 ( 1 ) + X 12 ( 2 ) ) ϕ X 22 ( 1 ) + X 22 ( 2 ) X 23 ( 1 ) + X 23 ( 2 ) X 24 ( 1 ) + X 24 ( 2 ) X 25 ( 1 ) + X 25 ( 2 ) ( X 13 ( 1 ) + X 13 ( 2 ) ) ϕ ( X 23 ( 1 ) + X 23 ( 2 ) ) ϕ X 33 ( 1 ) + X 33 ( 2 ) X 34 ( 1 ) + X 34 ( 2 ) X 35 ( 1 ) + X 35 ( 2 ) ( X 14 ( 1 ) + X 14 ( 2 ) ) ϕ ( X 24 ( 1 ) + X 24 ( 2 ) ) ϕ ( X 34 ( 1 ) + X 34 ( 2 ) ) ϕ X 44 ( 1 ) + X 44 ( 2 ) X 45 ( 1 ) + X 45 ( 2 ) ( X 15 ( 1 ) + X 15 ( 2 ) ) ϕ ( X 25 ( 1 ) + X 25 ( 2 ) ) ϕ ( X 35 ( 1 ) + X 35 ( 2 ) ) ϕ ( X 45 ( 1 ) + X 45 ( 2 ) ) ϕ X 55 ( 1 ) + X 55 ( 2 ) ( X 16 ( 1 ) + X 16 ( 2 ) ) ϕ ( X 26 ( 1 ) + X 26 ( 2 ) ) ϕ ( X 36 ( 1 ) + X 36 ( 2 ) ) ϕ ( X 46 ( 1 ) + X 46 ( 2 ) ) ϕ ( X 56 ( 1 ) + X 56 ( 2 ) ) ϕ ( X 17 ( 1 ) ) ϕ ( X 27 ( 1 ) ) ϕ ( X 37 ( 1 ) ) ϕ ( X 47 ( 1 ) ) ϕ ( X 57 ( 1 ) ) ϕ ( X 17 ( 2 ) ) ϕ ( X 27 ( 2 ) ) ϕ ( X 37 ( 2 ) ) ϕ ( X 47 ( 2 ) ) ϕ ( X 57 ( 2 ) ) ϕ ( X 18 ( 2 ) ) ϕ ( X 28 ( 2 ) ) ϕ ( X 38 ( 2 ) ) ϕ ( X 48 ( 2 ) ) ϕ ( X 58 ( 2 ) ) ϕ ( X 19 ( 2 ) ) ϕ ( X 29 ( 2 ) ) ϕ ( X 39 ( 2 ) ) ϕ ( X 49 ( 2 ) ) ϕ ( X 59 ( 2 ) ) ϕ ( X 1 , 10 ( 2 ) ) ϕ ( X 2 , 10 ( 2 ) ) ϕ ( X 3 , 10 ( 2 ) ) ϕ ( X 4 , 10 ( 2 ) ) ϕ ( X 5 , 10 ( 2 ) ) ϕ ( X 1 , 11 ( 2 ) ) ϕ ( X 2 , 11 ( 2 ) ) ϕ ( X 3 , 11 ( 2 ) ) ϕ ( X 4 , 11 ( 2 ) ) ϕ ( X 5 , 11 ( 2 ) ) ϕ ( X 1 , 12 ( 2 ) ) ϕ ( X 2 , 12 ( 2 ) ) ϕ ( X 3 , 12 ( 2 ) ) ϕ ( X 4 , 12 ( 2 ) ) ϕ ( X 5 , 12 ( 2 ) ) ϕ 0 0 0 0 0 ,
D 2 ( 1 ) = X 16 ( 1 ) + X 16 ( 2 ) X 17 ( 1 ) X 17 ( 2 ) X 18 ( 2 ) X 19 ( 2 ) X 1 , 10 ( 2 ) X 1 , 11 ( 2 ) X 1 , 12 ( 2 ) 0 X 26 ( 1 ) + X 26 ( 2 ) X 27 ( 1 ) X 27 ( 2 ) X 28 ( 2 ) X 29 ( 2 ) X 2 , 10 ( 2 ) X 2 , 11 ( 2 ) X 2 , 12 ( 2 ) 0 X 36 ( 1 ) + X 36 ( 2 ) X 37 ( 1 ) X 37 ( 2 ) X 38 ( 2 ) X 39 ( 2 ) X 3 , 10 ( 2 ) X 3 , 11 ( 2 ) X 3 , 12 ( 2 ) 0 X 46 ( 1 ) + X 46 ( 2 ) X 47 ( 1 ) X 47 ( 2 ) X 48 ( 2 ) X 49 ( 2 ) X 4 , 10 ( 2 ) X 4 , 11 ( 2 ) X 4 , 12 ( 2 ) 0 X 56 ( 1 ) + X 56 ( 2 ) X 57 ( 1 ) X 57 ( 2 ) X 58 ( 2 ) X 59 ( 2 ) X 5 , 10 ( 2 ) X 5 , 11 ( 2 ) X 5 , 12 ( 2 ) 0 X 66 ( 1 ) + X 66 ( 2 ) X 67 ( 1 ) X 67 ( 2 ) X 68 ( 2 ) X 69 ( 2 ) X 6 , 10 ( 2 ) X 6 , 11 ( 2 ) X 6 , 12 ( 2 ) 0 ( X 67 ( 1 ) ) ϕ X 77 ( 1 ) 0 0 0 0 0 0 0 ( X 67 ( 2 ) ) ϕ 0 X 77 ( 2 ) X 78 ( 2 ) X 79 ( 2 ) X 7 , 10 ( 2 ) X 7 , 11 ( 2 ) X 7 , 12 ( 2 ) 0 ( X 68 ( 2 ) ) ϕ 0 ( X 78 ( 2 ) ) ϕ X 88 ( 2 ) X 89 ( 2 ) X 8 , 10 ( 2 ) X 8 , 11 ( 2 ) X 8 , 12 ( 2 ) 0 ( X 69 ( 2 ) ) ϕ 0 ( X 79 ( 2 ) ) ϕ ( X 89 ( 2 ) ) ϕ X 9 , 9 ( 2 ) X 9 , 10 ( 2 ) X 9 , 11 ( 2 ) X 9 , 12 ( 2 ) 0 ( X 6 , 10 ( 2 ) ) ϕ 0 ( X 7 , 10 ( 2 ) ) ϕ ( X 8 , 10 ( 2 ) ) ϕ ( X 9 , 10 ( 2 ) ) ϕ X 10 , 10 ( 2 ) X 10 , 11 ( 2 ) X 10 , 12 ( 2 ) 0 ( X 6 , 11 ( 2 ) ) ϕ 0 ( X 7 , 11 ( 2 ) ) ϕ ( X 8 , 11 ( 2 ) ) ϕ ( X 9 , 11 ( 2 ) ) ϕ ( X 10 , 11 ( 2 ) ) ϕ X 11 , 11 ( 2 ) X 11 , 12 ( 2 ) 0 ( X 6 , 12 ( 2 ) ) ϕ 0 ( X 7 , 12 ( 2 ) ) ϕ ( X 8 , 12 ( 2 ) ) ϕ ( X 9 , 12 ( 2 ) ) ϕ ( X 10 , 12 ( 2 ) ) ϕ ( X 11 , 12 ( 2 ) ) ϕ X 12 , 12 ( 2 ) 0 0 0 0 0 0 0 0 0 0 ,
D 1 ( 2 ) = X 11 ( 2 ) + X 11 ( 3 ) X 12 ( 2 ) + X 12 ( 3 ) X 13 ( 2 ) + X 13 ( 3 ) X 14 ( 2 ) + X 14 ( 3 ) X 15 ( 2 ) X 17 ( 2 ) + X 15 ( 3 ) ( X 12 ( 2 ) + X 12 ( 3 ) ) ϕ X 22 ( 2 ) + X 22 ( 3 ) X 23 ( 2 ) + X 23 ( 3 ) X 24 ( 2 ) + X 24 ( 3 ) X 25 ( 2 ) X 27 ( 2 ) + X 25 ( 3 ) ( X 13 ( 2 ) + X 13 ( 3 ) ) ϕ ( X 23 ( 2 ) + X 23 ( 3 ) ) ϕ X 33 ( 2 ) + X 33 ( 3 ) X 34 ( 2 ) + X 34 ( 3 ) X 35 ( 2 ) X 37 ( 2 ) + X 35 ( 3 ) ( X 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( X 24 ( 2 ) + X 24 ( 3 ) ) ϕ ( X 34 ( 2 ) + X 34 ( 3 ) ) ϕ X 44 ( 2 ) + X 44 ( 3 ) X 45 ( 2 ) X 47 ( 2 ) + X 45 ( 3 ) ( X 15 ( 2 ) ) ϕ ( X 25 ( 2 ) ) ϕ ( X 35 ( 2 ) ) ϕ ( X 45 ( 2 ) ) ϕ X 55 ( 2 ) X 57 ( 2 ) ( X 17 ( 2 ) + X 15 ( 3 ) ) ϕ ( X 27 ( 2 ) + X 25 ( 3 ) ) ϕ ( X 37 ( 2 ) + X 35 ( 3 ) ) ϕ ( X 47 ( 2 ) + X 45 ( 3 ) ) ϕ ( X 57 ( 2 ) ) ϕ X 77 ( 2 ) + X 55 ( 3 ) ( X 18 ( 2 ) + X 16 ( 3 ) ) ϕ ( X 28 ( 2 ) + X 26 ( 3 ) ) ϕ ( X 38 ( 2 ) + X 36 ( 3 ) ) ϕ ( X 48 ( 2 ) + X 46 ( 3 ) ) ϕ ( X 58 ( 2 ) ) ϕ ( X 78 ( 2 ) + X 56 ( 3 ) ) ϕ ( X 19 ( 2 ) + X 17 ( 3 ) ) ϕ ( X 29 ( 2 ) + X 27 ( 3 ) ) ϕ ( X 39 ( 2 ) + X 37 ( 3 ) ) ϕ ( X 49 ( 2 ) + X 47 ( 3 ) ) ϕ ( X 59 ( 2 ) ) ϕ ( X 79 ( 2 ) + X 57 ( 3 ) ) ϕ ( X 1 , 10 ( 2 ) + X 18 ( 3 ) ) ϕ ( X 2 , 10 ( 2 ) + X 28 ( 3 ) ) ϕ ( X 3 , 10 ( 2 ) + X 38 ( 3 ) ) ϕ ( X 4 , 10 ( 2 ) + X 48 ( 3 ) ) ϕ ( X 5 , 10 ( 2 ) ) ϕ ( X 7 , 10 ( 2 ) + X 58 ( 3 ) ) ϕ ( X 1 , 11 ( 2 ) ) ϕ ( X 2 , 11 ( 2 ) ) ϕ ( X 3 , 11 ( 2 ) ) ϕ ( X 4 , 11 ( 2 ) ) ϕ ( X 5 , 11 ( 2 ) ) ϕ ( X 7 , 11 ( 2 ) ) ϕ ( X 1 , 13 ( 2 ) + X 19 ( 3 ) ) ϕ ( X 2 , 13 ( 2 ) + X 29 ( 3 ) ) ϕ ( X 3 , 13 ( 2 ) + X 39 ( 3 ) ) ϕ ( X 4 , 13 ( 2 ) + X 49 ( 3 ) ) ϕ ( X 5 , 13 ( 2 ) ) ϕ ( X 7 , 13 ( 2 ) + X 59 ( 3 ) ) ϕ ( X 1 , 14 ( 2 ) + X 1 , 10 ( 3 ) ) ϕ ( X 2 , 14 ( 2 ) + X 2 , 10 ( 3 ) ) ϕ ( X 3 , 14 ( 2 ) + X 3 , 10 ( 3 ) ) ϕ ( X 4 , 14 ( 2 ) + X 4 , 10 ( 3 ) ) ϕ ( X 5 , 14 ( 2 ) ) ϕ ( X 7 , 14 ( 2 ) + X 5 , 10 ( 3 ) ) ϕ ( X 1 , 15 ( 2 ) + X 1 , 11 ( 3 ) ) ϕ ( X 2 , 15 ( 2 ) + X 2 , 11 ( 3 ) ) ϕ ( X 3 , 15 ( 2 ) + X 3 , 11 ( 3 ) ) ϕ ( X 4 , 15 ( 2 ) + X 4 , 11 ( 3 ) ) ϕ ( X 5 , 15 ( 2 ) ) ϕ ( X 7 , 15 ( 2 ) + X 5 , 11 ( 3 ) ) ϕ ( X 1 , 16 ( 2 ) + X 1 , 12 ( 3 ) ) ϕ ( X 2 , 16 ( 2 ) + X 2 , 12 ( 3 ) ) ϕ ( X 3 , 16 ( 2 ) + X 3 , 12 ( 3 ) ) ϕ ( X 4 , 16 ( 2 ) + X 4 , 12 ( 3 ) ) ϕ ( X 5 , 16 ( 2 ) ) ϕ ( X 7 , 16 ( 2 ) + X 5 , 12 ( 3 ) ) ϕ ( X 1 , 17 ( 2 ) ) ϕ ( X 2 , 17 ( 2 ) ) ϕ ( X 3 , 17 ( 2 ) ) ϕ ( X 4 , 17 ( 2 ) ) ϕ ( X 5 , 17 ( 2 ) ) ϕ ( X 7 , 17 ( 2 ) ) ϕ ( X 1 , 13 ( 3 ) ) ϕ ( X 2 , 13 ( 3 ) ) ϕ ( X 3 , 13 ( 3 ) ) ϕ ( X 4 , 13 ( 3 ) ) ϕ 0 ( X 5 , 13 ( 3 ) ) ϕ ( X 1 , 14 ( 3 ) ) ϕ ( X 2 , 14 ( 3 ) ) ϕ ( X 3 , 14 ( 3 ) ) ϕ ( X 4 , 14 ( 3 ) ) ϕ 0 ( X 5 , 14 ( 3 ) ) ϕ ( X 1 , 15 ( 3 ) ) ϕ ( X 2 , 15 ( 3 ) ) ϕ ( X 3 , 15 ( 3 ) ) ϕ ( X 4 , 15 ( 3 ) ) ϕ 0 ( X 5 , 15 ( 3 ) ) ϕ ( X 1 , 16 ( 3 ) ) ϕ ( X 2 , 16 ( 3 ) ) ϕ ( X 3 , 16 ( 3 ) ) ϕ ( X 4 , 16 ( 3 ) ) ϕ 0 ( X 5 , 16 ( 3 ) ) ϕ 0 0 0 0 0 0 ,
D 2 ( 2 ) = X 18 ( 2 ) + X 16 ( 3 ) X 19 ( 2 ) + X 17 ( 3 ) X 1 , 10 ( 2 ) + X 18 ( 3 ) X 1 , 11 ( 2 ) X 1 , 13 ( 2 ) + X 19 ( 3 ) X 1 , 14 ( 2 ) + X 1 , 10 ( 3 ) X 28 ( 2 ) + X 26 ( 3 ) X 29 ( 2 ) + X 27 ( 3 ) X 2 , 10 ( 2 ) + X 28 ( 3 ) X 2 , 11 ( 2 ) X 2 , 13 ( 2 ) + X 29 ( 3 ) X 2 , 14 ( 2 ) + X 2 , 10 ( 3 ) X 38 ( 2 ) + X 36 ( 3 ) X 39 ( 2 ) + X 37 ( 3 ) X 3 , 10 ( 2 ) + X 38 ( 3 ) X 3 , 11 ( 2 ) X 3 , 13 ( 2 ) + X 39 ( 3 ) X 3 , 14 ( 2 ) + X 3 , 10 ( 3 ) X 48 ( 2 ) + X 46 ( 3 ) X 49 ( 2 ) + X 47 ( 3 ) X 4 , 10 ( 2 ) + X 48 ( 3 ) X 4 , 11 ( 2 ) X 4 , 13 ( 2 ) + X 49 ( 3 ) X 4 , 14 ( 2 ) + X 4 , 10 ( 3 ) X 58 ( 2 ) X 59 ( 2 ) X 5 , 10 ( 2 ) X 5 , 11 ( 2 ) X 5 , 13 ( 2 ) X 5 , 14 ( 2 ) X 78 ( 2 ) + X 56 ( 3 ) X 79 ( 2 ) + X 57 ( 3 ) X 7 , 10 ( 2 ) + X 58 ( 3 ) X 7 , 11 ( 2 ) X 7 , 13 ( 2 ) + X 59 ( 3 ) X 7 , 14 ( 2 ) + X 5 , 10 ( 3 ) X 88 ( 2 ) + X 66 ( 3 ) X 89 ( 2 ) + X 67 ( 3 ) X 8 , 10 ( 2 ) + X 68 ( 3 ) X 8 , 11 ( 2 ) X 8 , 13 ( 2 ) + X 69 ( 3 ) X 8 , 14 ( 2 ) + X 6 , 10 ( 3 ) ( X 89 ( 2 ) + X 67 ( 3 ) ) ϕ X 99 ( 2 ) + X 77 ( 3 ) X 9 , 10 ( 2 ) + X 78 ( 3 ) X 9 , 11 ( 2 ) X 9 , 13 ( 2 ) + X 79 ( 3 ) X 9 , 14 ( 2 ) + X 7 , 10 ( 3 ) ( X 8 , 10 ( 2 ) + X 68 ( 3 ) ) ϕ ( X 9 , 10 ( 2 ) + X 78 ( 3 ) ) ϕ X 10 , 10 ( 2 ) + X 88 ( 3 ) X 10 , 11 ( 2 ) X 10 , 13 ( 2 ) + X 89 ( 3 ) X 10 , 14 ( 2 ) + X 8 , 10 ( 3 ) ( X 8 , 11 ( 2 ) ) ϕ ( X 9 , 11 ( 2 ) ) ϕ ( X 10 , 11 ( 2 ) ) ϕ X 11 , 11 ( 2 ) X 11 , 13 ( 2 ) X 11 , 14 ( 2 ) ( X 8 , 13 ( 2 ) + X 69 ( 3 ) ) ϕ ( X 9 , 13 ( 2 ) + X 79 ( 3 ) ) ϕ ( X 10 , 13 ( 2 ) + X 89 ( 3 ) ) ϕ ( X 11 , 13 ( 2 ) ) ϕ X 13 , 13 ( 2 ) + X 99 ( 3 ) X 13 , 14 ( 2 ) + X 9 , 10 ( 3 ) ( X 8 , 14 ( 2 ) + X 6 , 10 ( 3 ) ) ϕ ( X 9 , 14 ( 2 ) + X 7 , 10 ( 3 ) ) ϕ ( X 10 , 14 ( 2 ) + X 8 , 10 ( 3 ) ) ϕ ( X 11 , 14 ( 2 ) ) ϕ ( X 13 , 14 ( 2 ) + X 9 , 10 ( 3 ) ) ϕ X 14 , 14 ( 2 ) + X 10 , 10 ( 3 ) ( X 8 , 15 ( 2 ) + X 6 , 11 ( 3 ) ) ϕ ( X 9 , 15 ( 2 ) + X 7 , 11 ( 3 ) ) ϕ ( X 10 , 15 ( 2 ) + X 8 , 11 ( 3 ) ) ϕ ( X 11 , 15 ( 2 ) ) ϕ ( X 13 , 15 ( 2 ) + X 9 , 11 ( 3 ) ) ϕ ( X 14 , 15 ( 2 ) + X 10 , 11 ( 3 ) ) ϕ ( X 8 , 16 ( 2 ) + X 6 , 12 ( 3 ) ) ϕ ( X 9 , 16 ( 2 ) + X 7 , 12 ( 3 ) ) ϕ ( X 10 , 16 ( 2 ) + X 8 , 12 ( 3 ) ) ϕ ( X 11 , 16 ( 2 ) ) ϕ ( X 13 , 16 ( 2 ) + X 9 , 12 ( 3 ) ) ϕ ( X 14 , 16 ( 2 ) + X 10 , 12 ( 3 ) ) ϕ ( X 8 , 17 ( 2 ) ) ϕ ( X 9 , 17 ( 2 ) ) ϕ ( X 10 , 17 ( 2 ) ) ϕ ( X 11 , 17 ( 2 ) ) ϕ ( X 13 , 17 ( 2 ) ) ϕ ( X 14 , 17 ( 2 ) ) ϕ ( X 6 , 13 ( 3 ) ) ϕ ( X 7 , 13 ( 3 ) ) ϕ ( X 8 , 13 ( 3 ) ) ϕ 0 ( X 9 , 13 ( 3 ) ) ϕ ( X 10 , 13 ( 3 ) ) ϕ ( X 6 , 14 ( 3 ) ) ϕ ( X 7 , 14 ( 3 ) ) ϕ ( X 8 , 14 ( 3 ) ) ϕ 0 ( X 9 , 14 ( 3 ) ) ϕ ( X 10 , 14 ( 3 ) ) ϕ ( X 6 , 15 ( 3 ) ) ϕ ( X 7 , 15 ( 3 ) ) ϕ ( X 8 , 15 ( 3 ) ) ϕ 0 ( X 9 , 15 ( 3 ) ) ϕ ( X 10 , 15 ( 3 ) ) ϕ ( X 6 , 16 ( 3 ) ) ϕ ( X 7 , 16 ( 3 ) ) ϕ ( X 8 , 16 ( 3 ) ) ϕ 0 ( X 9 , 16 ( 3 ) ) ϕ ( X 10 , 16 ( 3 ) ) ϕ 0 0 0 0 0 0 ,
D 3 ( 2 ) = X 1 , 15 ( 2 ) + X 1 , 11 ( 3 ) X 1 , 16 ( 2 ) + X 1 , 12 ( 3 ) X 1 , 17 ( 2 ) X 1 , 13 ( 3 ) X 1 , 14 ( 3 ) X 1 , 15 ( 3 ) X 1 , 16 ( 3 ) 0 X 2 , 15 ( 2 ) + X 2 , 11 ( 3 ) X 2 , 16 ( 2 ) + X 2 , 12 ( 3 ) X 2 , 17 ( 2 ) X 2 , 13 ( 3 ) X 2 , 14 ( 3 ) X 2 , 15 ( 3 ) X 2 , 16 ( 3 ) 0 X 3 , 15 ( 2 ) + X 3 , 11 ( 3 ) X 3 , 16 ( 2 ) + X 3 , 12 ( 3 ) X 3 , 17 ( 2 ) X 3 , 13 ( 3 ) X 3 , 14 ( 3 ) X 3 , 15 ( 3 ) X 3 , 16 ( 3 ) 0 X 4 , 15 ( 2 ) + X 4 , 11 ( 3 ) X 4 , 16 ( 2 ) + X 4 , 12 ( 3 ) X 4 , 17 ( 2 ) X 4 , 13 ( 3 ) X 4 , 14 ( 3 ) X 4 , 15 ( 3 ) X 4 , 16 ( 3 ) 0 X 5 , 15 ( 2 ) X 5 , 16 ( 2 ) X 5 , 17 ( 2 ) 0 0 0 0 0 X 7 , 15 ( 2 ) + X 5 , 11 ( 3 ) X 7 , 16 ( 2 ) + X 5 , 12 ( 3 ) X 7 , 17 ( 2 ) X 5 , 13 ( 3 ) X 5 , 14 ( 3 ) X 5 , 15 ( 3 ) X 5 , 16 ( 3 ) 0 X 8 , 15 ( 2 ) + X 6 , 11 ( 3 ) X 8 , 16 ( 2 ) + X 6 , 12 ( 3 ) X 8 , 17 ( 2 ) X 6 , 13 ( 3 ) X 6 , 14 ( 3 ) X 6 , 15 ( 3 ) X 6 , 16 ( 3 ) 0 X 9 , 15 ( 2 ) + X 7 , 11 ( 3 ) X 9 , 16 ( 2 ) + X 7 , 12 ( 3 ) X 9 , 17 ( 2 ) X 7 , 13 ( 3 ) X 7 , 14 ( 3 ) X 7 , 15 ( 3 ) X 7 , 16 ( 3 ) 0 X 10 , 15 ( 2 ) + X 8 , 11 ( 3 ) X 10 , 16 ( 2 ) + X 8 , 12 ( 3 ) X 10 , 17 ( 2 ) X 8 , 13 ( 3 ) X 8 , 14 ( 3 ) X 8 , 15 ( 3 ) X 8 , 16 ( 3 ) 0 X 11 , 15 ( 2 ) X 11 , 16 ( 2 ) X 11 , 17 ( 2 ) 0 0 0 0 0 X 13 , 15 ( 2 ) + X 9 , 11 ( 3 ) X 13 , 16 ( 2 ) + X 9 , 12 ( 3 ) X 13 , 17 ( 2 ) X 9 , 13 ( 3 ) X 9 , 14 ( 3 ) X 9 , 15 ( 3 ) X 9 , 16 ( 3 ) 0 X 14 , 15 ( 2 ) + X 10 , 11 ( 3 ) X 14 , 16 ( 2 ) + X 10 , 12 ( 3 ) X 14 , 17 ( 2 ) X 10 , 13 ( 3 ) X 10 , 14 ( 3 ) X 10 , 15 ( 3 ) X 10 , 16 ( 3 ) 0 X 15 , 15 ( 2 ) + X 11 , 11 ( 3 ) X 15 , 16 ( 2 ) + X 11 , 12 ( 3 ) X 15 , 17 ( 2 ) X 11 , 13 ( 3 ) X 11 , 14 ( 3 ) X 11 , 15 ( 3 ) X 11 , 16 ( 3 ) 0 ( X 15 , 16 ( 2 ) + X 11 , 12 ( 3 ) ) ϕ X 16 , 16 ( 2 ) + X 12 , 12 ( 3 ) X 16 , 17 ( 2 ) X 12 , 13 ( 3 ) X 12 , 14 ( 3 ) X 12 , 15 ( 3 ) X 12 , 16 ( 3 ) 0 ( X 15 , 17 ( 2 ) ) ϕ ( X 16 , 17 ( 2 ) ) ϕ X 17 , 17 ( 2 ) 0 0 0 0 0 ( X 11 , 13 ( 3 ) ) ϕ ( X 12 , 13 ( 3 ) ) ϕ 0 X 13 , 13 ( 3 ) X 13 , 14 ( 3 ) X 13 , 15 ( 3 ) X 13 , 16 ( 3 ) 0 ( X 11 , 14 ( 3 ) ) ϕ ( X 12 , 14 ( 3 ) ) ϕ 0 ( X 13 , 14 ( 3 ) ) ϕ X 14 , 14 ( 3 ) X 14 , 15 ( 3 ) X 14 , 16 ( 3 ) 0 ( X 11 , 15 ( 3 ) ) ϕ ( X 12 , 15 ( 3 ) ) ϕ 0 ( X 13 , 15 ( 3 ) ) ϕ ( X 14 , 15 ( 3 ) ) ϕ X 15 , 15 ( 3 ) X 15 , 16 ( 3 ) 0 ( X 11 , 16 ( 3 ) ) ϕ ( X 12 , 16 ( 3 ) ) ϕ 0 ( X 13 , 16 ( 3 ) ) ϕ ( X 14 , 16 ( 3 ) ) ϕ ( X 15 , 16 ( 3 ) ) ϕ X 16 , 16 ( 3 ) 0 0 0 0 0 0 0 0 0 ,
D 1 ( 3 ) = X 11 ( 3 ) + X 11 ( 4 ) X 12 ( 3 ) + X 12 ( 4 ) X 13 ( 3 ) X 15 ( 3 ) + X 13 ( 4 ) X 16 ( 3 ) + X 14 ( 4 ) X 17 ( 3 ) ( X 12 ( 3 ) + X 12 ( 4 ) ) ϕ X 22 ( 3 ) + X 22 ( 4 ) X 23 ( 3 ) X 25 ( 3 ) + X 23 ( 4 ) X 26 ( 3 ) + X 24 ( 4 ) X 27 ( 3 ) ( X 13 ( 3 ) ) ϕ ( X 23 ( 3 ) ) ϕ X 33 ( 3 ) X 35 ( 3 ) X 36 ( 3 ) X 37 ( 3 ) ( X 15 ( 3 ) + X 13 ( 4 ) ) ϕ ( X 25 ( 3 ) + X 23 ( 4 ) ) ϕ ( X 35 ( 3 ) ) ϕ X 55 ( 3 ) + X 33 ( 4 ) X 56 ( 3 ) + X 34 ( 4 ) X 57 ( 3 ) ( X 16 ( 3 ) + X 14 ( 4 ) ) ϕ ( X 26 ( 3 ) + X 24 ( 4 ) ) ϕ ( X 36 ( 3 ) ) ϕ ( X 56 ( 3 ) + X 34 ( 4 ) ) ϕ X 66 ( 3 ) + X 44 ( 4 ) X 67 ( 3 ) ( X 17 ( 3 ) ) ϕ ( X 27 ( 3 ) ) ϕ ( X 37 ( 3 ) ) ϕ ( X 57 ( 3 ) ) ϕ ( X 67 ( 3 ) ) ϕ X 77 ( 3 ) ( X 19 ( 3 ) + X 15 ( 4 ) ) ϕ ( X 29 ( 3 ) + X 25 ( 4 ) ) ϕ ( X 39 ( 3 ) ) ϕ ( X 59 ( 3 ) + X 35 ( 4 ) ) ϕ ( X 69 ( 3 ) + X 45 ( 4 ) ) ϕ ( X 79 ( 3 ) ) ϕ ( X 1 , 10 ( 3 ) + X 16 ( 4 ) ) ϕ ( X 2 , 10 ( 3 ) + X 26 ( 4 ) ) ϕ ( X 3 , 10 ( 3 ) ) ϕ ( X 5 , 10 ( 3 ) + X 36 ( 4 ) ) ϕ ( X 6 , 10 ( 3 ) + X 46 ( 4 ) ) ϕ ( X 7 , 10 ( 3 ) ) ϕ ( X 1 , 11 ( 3 ) ) ϕ ( X 2 , 11 ( 3 ) ) ϕ ( X 3 , 11 ( 3 ) ) ϕ ( X 5 , 11 ( 3 ) ) ϕ ( X 6 , 11 ( 3 ) ) ϕ ( X 7 , 11 ( 3 ) ) ϕ ( X 1 , 13 ( 3 ) + X 17 ( 4 ) ) ϕ ( X 2 , 13 ( 3 ) + X 27 ( 4 ) ) ϕ ( X 3 , 13 ( 3 ) ) ϕ ( X 5 , 13 ( 3 ) + X 37 ( 4 ) ) ϕ ( X 6 , 13 ( 3 ) + X 47 ( 4 ) ) ϕ ( X 7 , 13 ( 3 ) ) ϕ ( X 1 , 14 ( 3 ) + X 18 ( 4 ) ) ϕ ( X 2 , 14 ( 3 ) + X 28 ( 4 ) ) ϕ ( X 3 , 14 ( 3 ) ) ϕ ( X 5 , 14 ( 3 ) + X 38 ( 4 ) ) ϕ ( X 6 , 14 ( 3 ) + X 48 ( 4 ) ) ϕ ( X 7 , 14 ( 3 ) ) ϕ ( X 1 , 15 ( 3 ) ) ϕ ( X 2 , 15 ( 3 ) ) ϕ ( X 3 , 15 ( 3 ) ) ϕ ( X 5 , 15 ( 3 ) ) ϕ ( X 6 , 15 ( 3 ) ) ϕ ( X 7 , 15 ( 3 ) ) ϕ ( X 1 , 17 ( 3 ) + X 19 ( 4 ) ) ϕ ( X 2 , 17 ( 3 ) + X 29 ( 4 ) ) ϕ ( X 3 , 17 ( 3 ) ) ϕ ( X 5 , 17 ( 3 ) + X 39 ( 4 ) ) ϕ ( X 6 , 17 ( 3 ) + X 49 ( 4 ) ) ϕ ( X 7 , 17 ( 3 ) ) ϕ ( X 1 , 18 ( 3 ) + X 1 , 10 ( 4 ) ) ϕ ( X 2 , 18 ( 3 ) + X 2 , 10 ( 4 ) ) ϕ ( X 3 , 18 ( 3 ) ) ϕ ( X 5 , 18 ( 3 ) + X 3 , 10 ( 4 ) ) ϕ ( X 6 , 18 ( 3 ) + X 4 , 10 ( 4 ) ) ϕ ( X 7 , 18 ( 3 ) ) ϕ ( X 1 , 19 ( 3 ) ) ϕ ( X 2 , 19 ( 3 ) ) ϕ ( X 3 , 19 ( 3 ) ) ϕ ( X 5 , 19 ( 3 ) ) ϕ ( X 6 , 19 ( 3 ) ) ϕ ( X 7 , 19 ( 3 ) ) ϕ ( X 1 , 11 ( 4 ) ) ϕ ( X 2 , 11 ( 4 ) ) ϕ 0 ( X 3 , 11 ( 4 ) ) ϕ ( X 4 , 11 ( 4 ) ) ϕ 0 ( X 1 , 12 ( 4 ) ) ϕ ( X 2 , 12 ( 4 ) ) ϕ 0 ( X 3 , 12 ( 4 ) ) ϕ ( X 4 , 12 ( 4 ) ) ϕ 0 0 0 0 0 0 0 ,
D 2 ( 3 ) = X 19 ( 3 ) + X 15 ( 4 ) X 1 , 10 ( 3 ) + X 16 ( 4 ) X 1 , 11 ( 3 ) X 1 , 13 ( 3 ) + X 17 ( 4 ) X 1 , 14 ( 3 ) + X 18 ( 4 ) X 1 , 15 ( 3 ) X 29 ( 3 ) + X 25 ( 4 ) X 2 , 10 ( 3 ) + X 26 ( 4 ) X 2 , 11 ( 3 ) X 2 , 13 ( 3 ) + X 27 ( 4 ) X 2 , 14 ( 3 ) + X 28 ( 4 ) X 2 , 15 ( 3 ) X 39 ( 3 ) X 3 , 10 ( 3 ) X 3 , 11 ( 3 ) X 3 , 13 ( 3 ) X 3 , 14 ( 3 ) X 3 , 15 ( 3 ) X 59 ( 3 ) + X 35 ( 4 ) X 5 , 10 ( 3 ) + X 36 ( 4 ) X 5 , 11 ( 3 ) X 5 , 13 ( 3 ) + X 37 ( 4 ) X 5 , 14 ( 3 ) + X 38 ( 4 ) X 5 , 15 ( 3 ) X 69 ( 3 ) + X 45 ( 4 ) X 6 , 10 ( 3 ) + X 46 ( 4 ) X 6 , 11 ( 3 ) X 6 , 13 ( 3 ) + X 47 ( 4 ) X 6 , 14 ( 3 ) + X 48 ( 4 ) X 6 , 15 ( 3 ) X 79 ( 3 ) X 7 , 10 ( 3 ) X 7 , 11 ( 3 ) X 7 , 13 ( 3 ) X 7 , 14 ( 3 ) X 7 , 15 ( 3 ) X 99 ( 3 ) + X 55 ( 4 ) X 9 , 10 ( 3 ) + X 56 ( 4 ) X 9 , 11 ( 3 ) X 9 , 13 ( 3 ) + X 57 ( 4 ) X 9 , 14 ( 3 ) + X 58 ( 4 ) X 9 , 15 ( 3 ) ( X 9 , 10 ( 3 ) + X 56 ( 4 ) ) ϕ X 10 , 10 ( 3 ) + X 66 ( 4 ) X 10 , 11 ( 3 ) X 10 , 13 ( 3 ) + X 67 ( 4 ) X 10 , 14 ( 3 ) + X 68 ( 4 ) X 10 , 15 ( 3 ) ( X 9 , 11 ( 3 ) ) ϕ ( X 10 , 11 ( 3 ) ) ϕ X 11 , 11 ( 3 ) X 11 , 13 ( 3 ) X 11 , 14 ( 3 ) X 11 , 15 ( 3 ) ( X 9 , 13 ( 3 ) + X 57 ( 4 ) ) ϕ ( X 10 , 13 ( 3 ) + X 67 ( 4 ) ) ϕ ( X 11 , 13 ( 3 ) ) ϕ X 13 , 13 ( 3 ) + X 77 ( 4 ) X 13 , 14 ( 3 ) + X 78 ( 4 ) X 13 , 15 ( 3 ) ( X 9 , 14 ( 3 ) + X 58 ( 4 ) ) ϕ ( X 10 , 14 ( 3 ) + X 68 ( 4 ) ) ϕ ( X 11 , 14 ( 3 ) ) ϕ ( X 13 , 14 ( 3 ) + X 78 ( 4 ) ) ϕ X 14 , 14 ( 3 ) + X 88 ( 4 ) X 14 , 15 ( 3 ) ( X 9 , 15 ( 3 ) ) ϕ ( X 10 , 15 ( 3 ) ) ϕ ( X 11 , 15 ( 3 ) ) ϕ ( X 13 , 15 ( 3 ) ) ϕ ( X 14 , 15 ( 3 ) ) ϕ X 15 , 15 ( 3 ) ( X 9 , 17 ( 3 ) + X 59 ( 4 ) ) ϕ ( X 10 , 17 ( 3 ) + X 69 ( 4 ) ) ϕ ( X 11 , 17 ( 3 ) ) ϕ ( X 13 , 17 ( 3 ) + X 79 ( 4 ) ) ϕ ( X 14 , 17 ( 3 ) + X 89 ( 4 ) ) ϕ ( X 15 , 17 ( 3 ) ) ϕ ( X 9 , 18 ( 3 ) + X 5 , 10 ( 4 ) ) ϕ ( X 10 , 18 ( 3 ) + X 6 , 10 ( 4 ) ) ϕ ( X 11 , 18 ( 3 ) ) ϕ ( X 13 , 18 ( 3 ) + X 7 , 10 ( 4 ) ) ϕ ( X 14 , 18 ( 3 ) + X 8 , 10 ( 4 ) ) ϕ ( X 15 , 18 ( 3 ) ) ϕ ( X 9 , 19 ( 3 ) ) ϕ ( X 10 , 19 ( 3 ) ) ϕ ( X 11 , 19 ( 3 ) ) ϕ ( X 13 , 19 ( 3 ) ) ϕ ( X 14 , 19 ( 3 ) ) ϕ ( X 15 , 19 ( 3 ) ) ϕ ( X 5 , 11 ( 4 ) ) ϕ ( X 6 , 11 ( 4 ) ) ϕ 0 ( X 7 , 11 ( 4 ) ) ϕ ( X 8 , 11 ( 4 ) ) ϕ 0 ( X 5 , 12 ( 4 ) ) ϕ ( X 6 , 12 ( 4 ) ) ϕ 0 ( X 7 , 12 ( 4 ) ) ϕ ( X 8 , 12 ( 4 ) ) ϕ 0 0 0 0 0 0 0 ,
D 3 ( 3 ) = X 1 , 17 ( 3 ) + X 19 ( 4 ) X 1 , 18 ( 3 ) + X 1 , 10 ( 4 ) X 1 , 19 ( 3 ) X 1 , 11 ( 4 ) X 1 , 12 ( 4 ) 0 X 2 , 17 ( 3 ) + X 29 ( 4 ) X 2 , 18 ( 3 ) + X 2 , 10 ( 4 ) X 2 , 19 ( 3 ) X 2 , 11 ( 4 ) X 2 , 12 ( 4 ) 0 X 3 , 17 ( 3 ) X 3 , 18 ( 3 ) X 3 , 19 ( 3 ) 0 0 0 X 5 , 17 ( 3 ) + X 39 ( 4 ) X 5 , 18 ( 3 ) + X 3 , 10 ( 4 ) X 5 , 19 ( 3 ) X 3 , 11 ( 4 ) X 3 , 12 ( 4 ) 0 X 6 , 17 ( 3 ) + X 49 ( 4 ) X 6 , 18 ( 3 ) + X 4 , 10 ( 4 ) X 6 , 19 ( 3 ) X 4 , 11 ( 4 ) X 4 , 12 ( 4 ) 0 X 7 , 17 ( 3 ) X 7 , 18 ( 3 ) X 7 , 19 ( 3 ) 0 0 0 X 9 , 17 ( 3 ) + X 59 ( 4 ) X 9 , 18 ( 3 ) + X 5 , 10 ( 4 ) X 9 , 19 ( 3 ) X 5 , 11 ( 4 ) X 5 , 12 ( 4 ) 0 X 10 , 17 ( 3 ) + X 69 ( 4 ) X 10 , 18 ( 3 ) + X 6 , 10 ( 4 ) X 10 , 19 ( 3 ) X 6 , 11 ( 4 ) X 6 , 12 ( 4 ) 0 X 11 , 17 ( 3 ) X 11 , 18 ( 3 ) X 11 , 19 ( 3 ) 0 0 0 X 13 , 17 ( 3 ) + X 79 ( 4 ) X 13 , 18 ( 3 ) + X 7 , 10 ( 4 ) X 13 , 19 ( 3 ) X 7 , 11 ( 4 ) X 7 , 12 ( 4 ) 0 X 14 , 17 ( 3 ) + X 89 ( 4 ) X 14 , 18 ( 3 ) + X 8 , 10 ( 4 ) X 14 , 19 ( 3 ) X 8 , 11 ( 4 ) X 8 , 12 ( 4 ) 0 X 15 , 17 ( 3 ) X 15 , 18 ( 3 ) X 15 , 19 ( 3 ) 0 0 0 X 17 , 17 ( 3 ) + X 99 ( 4 ) X 17 , 18 ( 3 ) + X 9 , 10 ( 4 ) X 17 , 19 ( 3 ) X 9 , 11 ( 4 ) X 9 , 12 ( 4 ) 0 ( X 17 , 18 ( 3 ) + X 9 , 10 ( 4 ) ) ϕ X 18 , 18 ( 3 ) + X 10 , 10 ( 4 ) X 18 , 19 ( 3 ) X 10 , 11 ( 4 ) X 10 , 12 ( 4 ) 0 ( X 17 , 19 ( 3 ) ) ϕ ( X 18 , 19 ( 3 ) ) ϕ X 19 , 19 ( 3 ) 0 0 0 ( X 9 , 11 ( 4 ) ) ϕ ( X 10 , 11 ( 4 ) ) ϕ 0 X 11 , 11 ( 4 ) X 11 , 12 ( 4 ) 0 ( X 9 , 12 ( 4 ) ) ϕ ( X 10 , 12 ( 4 ) ) ϕ 0 ( X 11 , 12 ( 4 ) ) ϕ X 12 , 12 ( 4 ) 0 0 0 0 0 0 0 .
Observe that the matrices (11)–(14) are all defined in [20].
It follows from (11)–(14) that the general ϕ -skew-Hermitian solution to the system (4) is provided in the form (7)–(10). □
Example 1.
Given a system (1). We consider the general ϕ-skew-Hermitian solution to this system, where ϕ ( a ) = a j = j a j for a H . The quaternion matrices A i , B i , (i = 1, 2, 3), A 4 are given:
A 1 = i 0 1 + k 0 j k j + k 1 0 k , A 2 = j 2 i 0 3 k 0 i + j 5 + j 6 0 ,
A 3 = i 0 0 0 i + j 2 i 2 i + k k 0 , A 4 = 0 i + j 0 k 0 i + j k 2 j 0 i + 3 k ,
B 1 = 1 + i 3 0 0 i + k j k j 0 2 + k , B 2 = 0 k 2 j 3 i i j 0 5 k 0 j + k , B 3 = 0 k i + j 0 2 i 0 3 j 0 5 k .
The ϕ-skew-Hermitian matrices C i , (i = 1,2,3,4) are given:
C 1 = 4 j 6 + 11 i + 3 j 9 + 8 i + 16 j + 23 k 6 11 i + 3 j 18 j 24 10 i 12 j + 2 k 9 8 i + 16 j 23 k 24 + 10 i 12 j 2 k 15 j ,
C 2 = 15 j 6 + 2 i + 20 j + 3 k 10 10 i + 3 j 14 k 6 2 i + 20 j 3 k 45 j 36 50 i + 62 j + 39 k 10 + 10 i + 3 j + 14 k 36 + 50 i + 62 j 39 k 43 j ,
C 3 = 4 j 2 3 i + j 12 4 j 4 k 2 + 3 i + j 14 j 6 + 18 i 4 j 12 4 j + 4 k 6 18 i 4 j 39 j ,
C 4 = 2 j 2 + 2 i + 2 j 4 + 4 i + 4 k 2 2 i + 2 j 9 j 6 3 i 2 j 5 k 4 4 i 4 k 6 + 3 i 2 j + 5 k 12 j .
According to Theorem 1, the following ϕ-skew-Hermitian matrices satisfy the system
X 1 = ( X 1 ) ϕ = j 2 + 7 k 3 i + j k 2 7 k 5 j i + k 3 i + j + k i k 3 j ,
X 2 = ( X 2 ) ϕ = 2 j 1 + 2 i 0 1 2 i j 2 j + 3 k 0 2 j 3 k 3 j ,
X 3 = ( X 3 ) ϕ = j j 2 i j 3 j j + 3 k 2 i j 3 k 5 j , X 4 = ( X 4 ) ϕ = j i + j + 2 k k i + j 2 k j 0 k 0 2 j .

4. The β(ϕ)-Signature Bounds of the Solution X1 to the System (1)

In this section, we investigate the property of the solution X 1 to the system (1). Firstly, we consider the β ( ϕ )-signature bounds of the ϕ -skew-Hermitian solution X 1 to the system (1). The following Lemmas provide the β ( ϕ )-signature bounds and minimum rank of block matrices.
Lemma 2
([19]). Let M be a ϕ-skew-Hermitian block matrix
M = X A A ϕ B ,
where A H n × m and B = B ϕ H m × m are given, X H n × n is a variable ϕ-skew-Hermitian matrix. Then,
max X = X ϕ ln ± ( M ) = n + ln ± ( B ) , min X = X ϕ ln ± ( M ) = r A B ln ( B ) .
Lemma 3
([26,27,28,29]). Let N be a block matrix
N = A B D Y ,
where A, B and D are given quaternion matrices, Y H n × m is a variable matrix. Then,
min Y r ( N ) = r A B + r A D r ( A ) .
The following Theorem derives the β ( ϕ )-signature bounds of the solution X 1 to the system (1).
Theorem 2.
Assume that the system (1) has a ϕ-skew-Hermitian solution ( X 1 , X 2 , X 3 , X 4 ) H t 1 × t 1 × H t 2 × t 2 × H t 3 × t 3 × H t 4 × t 4 . We denote
S = { X 1 = ( X 1 ) ϕ H t 1 × t 1 A i X i ( A i ) ϕ + B i X i + 1 ( B i ) ϕ = C i , ( i = 1 , 2 , 3 ) , A 4 X 4 ( A 4 ) ϕ = C 4 } .
Then, we can obtain
max ln ± ( X 1 ) = t 1 r A 1 r B 1 0 0 A 2 B 2 0 0 A 3 B 3 r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1
+ r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 + ln ± C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1 ,
min ln ± ( X 1 ) = r ( B 1 ) ϕ C 1 r A 2 0 0 ( B 1 ) ϕ B 1 C 1 + r ( B 2 ) ϕ 0 0 C 2 A 2 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 B 1 C 1
r A 3 0 0 0 0 ( B 2 ) ϕ 0 0 B 2 C 2 A 2 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 B 1 C 1 + r ( B 3 ) ϕ 0 0 0 0 C 3 A 3 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 B 2 C 2 A 2 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 B 1 C 1
r A 4 0 0 0 0 0 0 ( B 3 ) ϕ 0 0 0 0 B 3 C 3 A 3 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 B 2 C 2 A 2 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 B 1 C 1 + ln ± C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1 .
Proof. 
According to Theorem 1, the ϕ -skew-Hermitian solution X 1 can be written as
X 1 = T ^ 1 X ^ 1 ( T ^ 1 ) ϕ ,
we have
ln ± ( X 1 ) X 1 S = ln ± ( T ^ 1 X ^ 1 ( T ^ 1 ) ϕ ) = ln ± ( X ^ 1 ) .
Thus, in order to study the β ( ϕ )-signature bounds of X 1 under S, we just have to consider the β ( ϕ )-signature bounds of X ^ 1 . Assume X ^ 1 = ( X ^ 1 ( 1 ) , X ^ 1 ( 2 ) ) , where
X ^ 1 ( 1 ) = n 1 n 2 n 3 n 1 n 2 n 3 n 4 n 5 n 6 n 7 t 1 r a 1 ( D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) ϕ ( D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ) ϕ ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 16 ( 1 ) X 16 ( 2 ) ) ϕ ( D 26 ( 1 ) X 26 ( 2 ) ) ϕ ( D 36 ( 1 ) X 36 ( 2 ) ) ϕ ( D 17 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( X 18 ( 1 ) ) ϕ ( X 28 ( 1 ) ) ϕ ( X 38 ( 1 ) ) ϕ ) ,
X ^ 1 ( 2 ) = n 4 n 5 n 6 n 7 t 1 r a 1 n 1 n 2 n 3 n 4 n 5 n 6 n 7 t 1 r a 1 ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 15 ( 1 ) D 15 ( 2 ) D 16 ( 1 ) X 16 ( 2 ) D 17 ( 1 ) X 18 ( 1 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) D 25 ( 1 ) D 25 ( 2 ) D 26 ( 1 ) X 26 ( 2 ) D 27 ( 1 ) X 28 ( 1 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) D 35 ( 1 ) D 35 ( 2 ) D 36 ( 1 ) X 36 ( 2 ) D 37 ( 1 ) X 38 ( 1 ) D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) D 45 ( 1 ) D 45 ( 2 ) D 46 ( 1 ) X 46 ( 2 ) D 47 ( 1 ) X 48 ( 1 ) ( D 45 ( 1 ) D 45 ( 2 ) ) ϕ D 55 ( 1 ) D 55 ( 2 ) D 56 ( 1 ) X 56 ( 2 ) D 57 ( 1 ) X 58 ( 1 ) ( D 46 ( 1 ) X 46 ( 2 ) ) ϕ ( D 56 ( 1 ) X 56 ( 2 ) ) ϕ D 66 ( 1 ) X 66 ( 2 ) D 67 ( 1 ) X 68 ( 1 ) ( D 47 ( 1 ) ) ϕ ( D 57 ( 1 ) ) ϕ ( D 67 ( 1 ) ) ϕ D 77 ( 1 ) X 78 ( 1 ) ( X 48 ( 1 ) ) ϕ ( X 58 ( 1 ) ) ϕ ( X 68 ( 1 ) ) ϕ ( X 78 ( 1 ) ) ϕ X 88 ( 1 ) ) .
We treat matrix X ^ 1 as a block matrix, using the Lemma 2 and Lemma 3 to get the β ( ϕ )-signature bounds of the ϕ -skew-Hermitian matrix X ^ 1 , which is equivalent to the β ( ϕ )-signature bounds of the ϕ -skew-Hermitian solution X 1 . The specific steps are as follows.
Step 1. We treat the variable ϕ -skew-Hermitian matrix X 88 ( 1 ) of X ^ 1 as the matrix block X in (15). According to Lemma 2, we derive
max X 88 ( 1 ) ln ± ( X ^ 1 ) = t 1 r a 1 + ln ± ( Ψ 1 ) , min X 88 ( 1 ) ln ± ( X ^ 1 ) = r ( Ψ ) ln ( Ψ 1 ) ,
assume Ψ = ( Ψ ( 1 ) , Ψ ( 2 ) ) , Ψ 1 = ( Ψ 1 ( 1 ) , Ψ 1 ( 2 ) ) , where
Ψ ( 1 ) = n 7 n 1 n 2 n 7 n 1 n 2 n 3 n 4 n 5 n 6 t 1 r a 1 ( D 77 ( 1 ) ( D 17 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ D 17 ( 1 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 27 ( 1 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) D 37 ( 1 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 47 ( 1 ) ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) ϕ D 57 ( 1 ) ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ D 67 ( 1 ) ( D 16 ( 1 ) X 16 ( 2 ) ) ϕ ( D 26 ( 1 ) X 26 ( 2 ) ) ϕ ( X 78 ( 1 ) ) ϕ ( X 18 ( 1 ) ) ϕ ( X 28 ( 1 ) ) ϕ ) ,
Ψ ( 2 ) = n 3 n 4 n 5 n 6 n 7 n 1 n 2 n 3 n 4 n 5 n 6 t 1 r a 1 ( ( D 37 ( 1 ) ) ϕ ( D 47 ( 1 ) ) ϕ ( D 57 ( 1 ) ) ϕ ( D 67 ( 1 ) ) ϕ D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 15 ( 1 ) D 15 ( 2 ) D 16 ( 1 ) X 16 ( 2 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) D 25 ( 1 ) D 25 ( 2 ) D 26 ( 1 ) X 26 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) D 35 ( 1 ) D 35 ( 2 ) D 36 ( 1 ) X 36 ( 2 ) ( D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ) ϕ D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) D 45 ( 1 ) D 45 ( 2 ) D 46 ( 1 ) X 46 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 45 ( 1 ) D 45 ( 2 ) ) ϕ D 55 ( 1 ) D 55 ( 2 ) D 56 ( 1 ) X 56 ( 2 ) ( D 36 ( 1 ) X 36 ( 2 ) ) ϕ ( D 46 ( 1 ) X 46 ( 2 ) ) ϕ ( D 56 ( 1 ) X 56 ( 2 ) ) ϕ D 66 ( 1 ) X 66 ( 2 ) ( X 38 ( 1 ) ) ϕ ( X 48 ( 1 ) ) ϕ ( X 58 ( 1 ) ) ϕ ( X 68 ( 1 ) ) ϕ ) ,
Ψ 1 ( 1 ) = n 7 n 1 n 2 n 7 n 1 n 2 n 3 n 4 n 5 n 6 ( D 77 ( 1 ) ( D 17 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ D 17 ( 1 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 27 ( 1 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) D 37 ( 1 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 47 ( 1 ) ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) ϕ D 57 ( 1 ) ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ D 67 ( 1 ) ( D 16 ( 1 ) X 16 ( 2 ) ) ϕ ( D 26 ( 1 ) X 26 ( 2 ) ) ϕ ) ,
Ψ 1 ( 2 ) = n 3 n 4 n 5 n 6 n 7 n 1 n 2 n 3 n 4 n 5 n 6 ( ( D 37 ( 1 ) ) ϕ ( D 47 ( 1 ) ) ϕ ( D 57 ( 1 ) ) ϕ ( D 67 ( 1 ) ) ϕ D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 15 ( 1 ) D 15 ( 2 ) D 16 ( 1 ) X 16 ( 2 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) D 25 ( 1 ) D 25 ( 2 ) D 26 ( 1 ) X 26 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) D 35 ( 1 ) D 35 ( 2 ) D 36 ( 1 ) X 36 ( 2 ) ( D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ) ϕ D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) D 45 ( 1 ) D 45 ( 2 ) D 46 ( 1 ) X 46 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 45 ( 1 ) D 45 ( 2 ) ) ϕ D 55 ( 1 ) D 55 ( 2 ) D 56 ( 1 ) X 56 ( 2 ) ( D 36 ( 1 ) X 36 ( 2 ) ) ϕ ( D 46 ( 1 ) X 46 ( 2 ) ) ϕ ( D 56 ( 1 ) X 56 ( 2 ) ) ϕ D 66 ( 1 ) X 66 ( 2 ) ) .
Then, we treat the matrix Ψ as a block matrix. According to Lemma 3, we have
min ( X 78 ( 1 ) , X 18 ( 1 ) , X 28 ( 1 ) , X 38 ( 1 ) , X 48 ( 1 ) , X 58 ( 1 ) , X 68 ( 1 ) ) r ( Ψ ) = r ( Ψ 1 ) .
Thus, we can obtain
max X 88 ( 1 ) , X 78 ( 1 ) X 18 ( 1 ) X 28 ( 1 ) X 38 ( 1 ) X 48 ( 1 ) X 58 ( 1 ) X 68 ( 1 ) ln ± ( X ^ 1 ) = t 1 r a 1 + ln ± ( Ψ 1 ) , min X 88 ( 1 ) , X 78 ( 1 ) X 18 ( 1 ) X 28 ( 1 ) X 38 ( 1 ) X 48 ( 1 ) X 58 ( 1 ) X 68 ( 1 ) ln ± ( X ^ 1 ) = ln ± ( Ψ 1 ) .
Step 2. We treating the variable ϕ -skew-Hermitian matrix D 66 ( 1 ) X 66 ( 2 ) of Ψ 1 as the matrix block X in (15). According to Lemma 2, we provide
max D 66 ( 1 ) X 66 ( 2 ) ln ± ( Ψ 1 ) = n 6 + ln ± ( Ψ 3 ) , min D 66 ( 1 ) X 66 ( 2 ) ln ± ( Ψ 1 ) = r ( Ψ 2 ) ln ( Ψ 3 ) ,
assume Ψ 2 = ( Ψ 2 ( 1 ) , Ψ 2 ( 2 ) ) , Ψ 3 = ( Ψ 3 ( 1 ) , Ψ 3 ( 2 ) ) , where
Ψ 2 ( 1 ) = n 7 n 1 n 2 n 7 n 1 n 2 n 3 n 5 n 4 n 6 ( D 77 ( 1 ) ( D 17 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ D 17 ( 1 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 27 ( 1 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) D 37 ( 1 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 57 ( 1 ) ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ D 47 ( 1 ) ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) ϕ D 67 ( 1 ) ( D 16 ( 1 ) X 16 ( 2 ) ) ϕ ( D 26 ( 1 ) X 26 ( 2 ) ) ϕ ) ,
Ψ 2 ( 2 ) = n 3 n 5 n 4 n 7 n 1 n 2 n 3 n 5 n 4 n 6 ( ( D 37 ( 1 ) ) ϕ ( D 57 ( 1 ) ) ϕ ( D 47 ( 1 ) ) ϕ D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 15 ( 1 ) D 15 ( 2 ) D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) D 25 ( 1 ) D 25 ( 2 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 35 ( 1 ) D 35 ( 2 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 55 ( 1 ) D 55 ( 2 ) ( D 45 ( 1 ) D 45 ( 2 ) ) ϕ ( D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ) ϕ D 45 ( 1 ) D 45 ( 2 ) D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) ( D 36 ( 1 ) X 36 ( 2 ) ) ϕ ( D 56 ( 1 ) X 56 ( 2 ) ) ϕ ( D 46 ( 1 ) X 46 ( 2 ) ) ϕ ) ,
Ψ 3 ( 1 ) = n 7 n 1 n 2 n 7 n 1 n 2 n 3 n 5 n 4 ( D 77 ( 1 ) ( D 17 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ D 17 ( 1 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 27 ( 1 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) D 37 ( 1 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 57 ( 1 ) ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ D 47 ( 1 ) ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) ϕ ) ,
Ψ 3 ( 2 ) = n 3 n 5 n 4 n 7 n 1 n 2 n 3 n 5 n 4 ( ( D 37 ( 1 ) ) ϕ ( D 57 ( 1 ) ) ϕ ( D 47 ( 1 ) ) ϕ D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 15 ( 1 ) D 15 ( 2 ) D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) D 25 ( 1 ) D 25 ( 2 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 35 ( 1 ) D 35 ( 2 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 55 ( 1 ) D 55 ( 2 ) ( D 45 ( 1 ) D 45 ( 2 ) ) ϕ ( D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ) ϕ D 45 ( 1 ) D 45 ( 2 ) D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) ) .
Then, we treat the matrix Ψ 2 as a block matrix. According to Lemma 3, we derive
min ( D 16 ( 1 ) X 16 ( 2 ) , D 26 ( 1 ) X 26 ( 2 ) , D 36 ( 1 ) X 36 ( 2 ) , D 56 ( 1 ) X 56 ( 2 ) , D 46 ( 1 ) X 46 ( 2 ) ) r ( Ψ 2 ) = r ( Ψ 3 ) + r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) D 67 ( 1 ) r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) .
Thus, we can provide
max D 66 ( 1 ) X 66 ( 2 ) , D 16 ( 1 ) X 16 ( 2 ) D 26 ( 1 ) X 26 ( 2 ) D 36 ( 1 ) X 36 ( 2 ) D 56 ( 1 ) X 56 ( 2 ) D 46 ( 1 ) X 46 ( 2 ) ln ± ( Ψ 1 ) = n 6 + ln ± ( Ψ 3 ) ,
min D 66 ( 1 ) X 66 ( 2 ) , D 16 ( 1 ) X 16 ( 2 ) D 26 ( 1 ) X 26 ( 2 ) D 36 ( 1 ) X 36 ( 2 ) D 56 ( 1 ) X 56 ( 2 ) D 46 ( 1 ) X 46 ( 2 ) ln ± ( Ψ 1 ) = ln ± ( Ψ 3 ) + r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) D 67 ( 1 ) r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) .
Step 3. Using Lemma 2, Lemma 3 and the similar methods in Step 1 and Step 2 (the specific proof process please see Appendix A), we establish
max ln ± ( X ^ 1 ) = t 1 r a 1 + n 6 + n 4 + n 2
+ ln ± D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( D 17 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) ,
min ln ± ( X ^ 1 ) = r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) D 67 ( 1 ) r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 47 ( 1 ) D 45 ( 1 ) D 45 ( 2 ) r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 )
+ r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 )
+ ln ± D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( D 17 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) .
Step 4. The ranks and β ( ϕ )-signature of matrices in (4.5) and (4.6) can be represented by the following expression
r ( B 1 ) ϕ C 1 = r B 1 + r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) D 67 ( 1 ) , r A 2 0 0 ( B 1 ) ϕ B 1 C 1 = r A 2 B 1 + r B 1 + r D 77 ( 1 ) D 17 ( 1 ) D 27 ( 1 ) D 37 ( 1 ) D 57 ( 1 ) D 47 ( 1 ) ,
r ( B 2 ) ϕ 0 0 C 2 A 2 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 B 1 C 1 = r A 2 B 1 + r B 2 A 2 0 B 1 + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 47 ( 1 ) D 45 ( 1 ) D 45 ( 2 ) ,
r A 3 0 0 0 0 ( B 2 ) ϕ 0 0 B 2 C 2 A 2 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 B 1 C 1 = r A 3 0 B 2 A 2 0 B 1 + r B 2 A 2 0 B 1 + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) ,
r ( B 3 ) ϕ 0 0 0 0 C 3 A 3 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 B 2 C 2 A 2 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 B 1 C 1 = r A 3 0 B 2 A 2 0 B 1 + r B 3 A 3 0 0 B 2 A 2 0 0 B 1 + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ,
r A 4 0 0 0 0 0 0 ( B 3 ) ϕ 0 0 0 0 B 3 C 3 A 3 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 B 2 C 2 A 2 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 B 1 C 1
= r B 3 A 3 0 0 B 2 A 2 0 0 B 1 + r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1 + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ,
ln ± C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1 + ln ± D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( D 17 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) ,
n 2 = r B 1 0 A 2 B 2 + r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 r A 1 B 1 0 0 A 2 B 2 r B 1 0 0 A 2 B 2 0 0 A 3 B 3 ,
n 4 = r B 1 + r A 1 B 1 0 0 A 2 B 2 r A 1 B 1 r B 1 0 A 2 B 2 ,
n 6 = r A 1 B 1 r B 1 , r a 1 = r A 1 .
The above results indicate that the β ( ϕ )-signature bounds of the ϕ -skew-Hermitian matrix X ^ 1 can be expressed as
max ln ± ( X ^ 1 ) = t 1 r A 1 r B 1 0 0 A 2 B 2 0 0 A 3 B 3 r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1
+ r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 + ln ± C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1 ,
min ln ± ( X ^ 1 ) = r ( B 1 ) ϕ C 1 r A 2 0 0 ( B 1 ) ϕ B 1 C 1 + r ( B 2 ) ϕ 0 0 C 2 A 2 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 B 1 C 1
r A 3 0 0 0 0 ( B 2 ) ϕ 0 0 B 2 C 2 A 2 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 B 1 C 1 + r ( B 3 ) ϕ 0 0 0 0 C 3 A 3 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 B 2 C 2 A 2 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 B 1 C 1
r A 4 0 0 0 0 0 0 ( B 3 ) ϕ 0 0 0 0 B 3 C 3 A 3 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 B 2 C 2 A 2 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 B 1 C 1 + ln ± C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1 .
In conclusion, Theorem 2 is proved. □
Based on Theorem 2, we derive some necessary and sufficient conditions for the system (1) to have β ( ϕ )-positive definite, β ( ϕ )-positive semidefinite, β ( ϕ )-negative definite and β ( ϕ )-negative semidefinite solutions.
Theorem 3.
Assume that the system (1) has a ϕ-skew-Hermitian solution ( X 1 , X 2 , X 3 , X 4 ) H t 1 × t 1 × H t 2 × t 2 × H t 3 × t 3 × H t 4 × t 4 . We can derive the following conclusions.
a There is a β(ϕ)-positive definite solution X 1 if and only if
ln + C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 1 + r B 1 0 0 A 2 B 2 0 0 A 3 B 3 + r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1 r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 .
b There is a β(ϕ)-negative definite solution X 1 if and only if
ln C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 1 + r B 1 0 0 A 2 B 2 0 0 A 3 B 3 + r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1 r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 .
c There is a β(ϕ)-positive semidefinite solution X 1 if and only if
ln + C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 2 0 0 ( B 1 ) ϕ B 1 C 1 + r A 3 0 0 0 0 ( B 2 ) ϕ 0 0 B 2 C 2 A 2 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 B 1 C 1 + r A 4 0 0 0 0 0 0 ( B 3 ) ϕ 0 0 0 0 B 3 C 3 A 3 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 B 2 C 2 A 2 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 B 1 C 1
r ( B 1 ) ϕ C 1 r ( B 2 ) ϕ 0 0 C 2 A 2 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 B 1 C 1 r ( B 3 ) ϕ 0 0 0 0 C 3 A 3 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 B 2 C 2 A 2 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 B 1 C 1 .
d There is a β(ϕ)-negative semidefinite solution X 1 if and only if
ln C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 2 0 0 ( B 1 ) ϕ B 1 C 1 + r A 3 0 0 0 0 ( B 2 ) ϕ 0 0 B 2 C 2 A 2 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 B 1 C 1 + r A 4 0 0 0 0 0 0 ( B 3 ) ϕ 0 0 0 0 B 3 C 3 A 3 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 B 2 C 2 A 2 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 B 1 C 1
r ( B 1 ) ϕ C 1 r ( B 2 ) ϕ 0 0 C 2 A 2 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 B 1 C 1 r ( B 3 ) ϕ 0 0 0 0 C 3 A 3 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 B 2 C 2 A 2 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 B 1 C 1 .
e All the solutions X 1 are β(ϕ)-positive definite if and only if
r ( B 1 ) ϕ C 1 r A 2 0 0 ( B 1 ) ϕ B 1 C 1 + r ( B 2 ) ϕ 0 0 C 2 A 2 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 B 1 C 1
r A 3 0 0 0 0 ( B 2 ) ϕ 0 0 B 2 C 2 A 2 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 B 1 C 1 + r ( B 3 ) ϕ 0 0 0 0 C 3 A 3 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 B 2 C 2 A 2 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 B 1 C 1
r A 4 0 0 0 0 0 0 ( B 3 ) ϕ 0 0 0 0 B 3 C 3 A 3 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 B 2 C 2 A 2 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 B 1 C 1 + ln C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1 = t 1 .
f All the solutions X 1 are β(ϕ)-negative definite if and only if
r ( B 1 ) ϕ C 1 r A 2 0 0 ( B 1 ) ϕ B 1 C 1 + r ( B 2 ) ϕ 0 0 C 2 A 2 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 B 1 C 1
r A 3 0 0 0 0 ( B 2 ) ϕ 0 0 B 2 C 2 A 2 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 B 1 C 1 + r ( B 3 ) ϕ 0 0 0 0 C 3 A 3 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 B 2 C 2 A 2 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 B 1 C 1
r A 4 0 0 0 0 0 0 ( B 3 ) ϕ 0 0 0 0 B 3 C 3 A 3 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 B 2 C 2 A 2 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 B 1 C 1 + ln + C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1 = t 1 .
g All the solutions X 1 are β(ϕ)-positive semidefinite if and only if
t 1 + ln C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 1 + r B 1 0 0 A 2 B 2 0 0 A 3 B 3 + r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1 r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 .
h All the solutions X 1 are β(ϕ)-negative semidefinite if and only if
t 1 + ln + C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 1 + r B 1 0 0 A 2 B 2 0 0 A 3 B 3 + r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1 r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 .
Proof. 
According to Theorem 2, the system (1) has a β ( ϕ )-positive definite solution X 1 if and only if
max ln + ( X 1 ) = t 1 .
It follows from Theorem 2 that
max ln ± ( X 1 ) = t 1 r A 1 r B 1 0 0 A 2 B 2 0 0 A 3 B 3 r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1
+ r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 + ln ± C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1 = t 1 .
Then, we can obtain that there is a β ( ϕ )-positive definite solution X 1 if and only if
ln + C 4 A 4 0 0 0 0 0 ( A 4 ) ϕ 0 ( B 3 ) ϕ 0 0 0 0 0 B 3 C 3 A 3 0 0 0 0 0 ( A 3 ) ϕ 0 ( B 2 ) ϕ 0 0 0 0 0 B 2 C 2 A 2 0 0 0 0 0 ( A 2 ) ϕ 0 ( B 1 ) ϕ 0 0 0 0 0 B 1 C 1
= r A 1 + r B 1 0 0 A 2 B 2 0 0 A 3 B 3 + r A 4 0 0 B 3 A 3 0 0 B 2 A 2 0 0 B 1 r A 1 B 1 0 0 0 A 2 B 2 0 0 0 A 3 B 3 .
Hence, we can prove the statements (a). In a similar way, we can obtain (b)–(h). □

5. Conclusions

We have provided the general solution to the system (1). Furthermore, we have given the β ( ϕ )-signature bounds of the ϕ -skew-Hermitian solution to the system (1). Finally, we have presented some necessary and sufficient conditions for the system (1) to have β ( ϕ )-positive definite, β ( ϕ )-positive semidefinite, β ( ϕ )-negative definite and β ( ϕ )-negative semidefinite solutions.

Author Contributions

Methodology, Z.-H.H. and X.-N.Z.; software, W.-L.Q.; writing—original draft preparation, Z.-H.H. and X.-N.Z.; writing—review and editing, Z.-H.H., X.-N.Z. and S.-W.Y.; supervision, S.-W.Y.; project administration, Z.-H.H. All authors have read and agreed to the published version of the manuscript.

Funding

This research was supported by the National Natural Science Foundation of China (Grant no. 12271338, 11971294 and 11801354).

Data Availability Statement

Not applicable.

Conflicts of Interest

The authors declare no conflict of interest.

Appendix A. The Specific Proof Process for Theorem Step 3

Step 3 (1). Treating the variable ϕ -skew-Hermitian matrix D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) of Ψ 3 is the matrix block X in (15), using Lemma 2 we have
max D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) ln ± ( Ψ 3 ) = n 4 + ln ± ( Ψ 5 ) , min D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) ln ± ( Ψ 3 ) = r ( Ψ 4 ) ln ( Ψ 5 ) ,
where
Ψ 4 = n 7 n 5 n 1 n 3 n 2 n 7 n 5 n 1 n 3 n 2 n 4 ( D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 17 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) D 47 ( 1 ) D 45 ( 1 ) D 45 ( 2 ) ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) ) ϕ ( D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) ) ϕ ( D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) ϕ ) ,
Ψ 5 = n 7 n 5 n 1 n 3 n 2 n 7 n 5 n 1 n 3 n 2 ( D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 17 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( D 27 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 25 ( 1 ) D 25 ( 2 ) ) ϕ D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ) ϕ D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) ) .
Then, we treat the matrix Ψ 4 as a block matrix, using Lemma 3 we have
min ( D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) , D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) , D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ) r ( Ψ 4 ) = r ( Ψ 5 ) + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 47 ( 1 ) D 45 ( 1 ) D 45 ( 2 ) r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) .
Thus, we can get
max D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) , D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ln ± ( Ψ 3 ) = n 4 + ln ± ( Ψ 5 ) ,
min D 44 ( 1 ) D 44 ( 2 ) + X 44 ( 3 ) , D 14 ( 1 ) D 14 ( 2 ) + X 14 ( 3 ) D 34 ( 1 ) D 34 ( 2 ) + X 34 ( 3 ) D 24 ( 1 ) D 24 ( 2 ) + X 24 ( 3 ) ln ± ( Ψ 3 ) = ln ± ( Ψ 5 ) + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 47 ( 1 ) D 45 ( 1 ) D 45 ( 2 ) r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) .
Step 3 (2). Treating the variable ϕ -skew-Hermitian matrix D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) of Ψ 5 is the matrix block X in (15), using Lemma 2 we have
max D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) ln ± ( Ψ 5 ) = n 2 + ln ± ( Ψ 7 ) , min D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) ln ± ( Ψ 5 ) = r ( Ψ 6 ) ln ( Ψ 7 ) ,
where
Ψ 6 = n 7 n 5 n 3 n 1 n 7 n 5 n 3 n 1 n 2 ( D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( D 17 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) ( D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ) ϕ ) ,
Ψ 7 = n 7 n 5 n 3 n 1 n 7 n 5 n 3 n 1 ( D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ ( D 17 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ ( D 15 ( 1 ) D 15 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) ( D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) ) ϕ D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 11 ( 1 ) D 11 ( 2 ) + D 11 ( 3 ) D 11 ( 4 ) ) .
Then, we treat the matrix Ψ 6 as a block matrix, using Lemma 3 we have
min D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) r ( Ψ 6 ) = r ( Ψ 7 ) + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 )
r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) .
Thus, we can get
max D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) , D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ln ± ( Ψ 5 ) = n 2 + ln ± ( Ψ 7 ) ,
min D 22 ( 1 ) D 22 ( 2 ) + D 22 ( 3 ) X 22 ( 4 ) , D 12 ( 1 ) D 12 ( 2 ) + D 12 ( 3 ) X 12 ( 4 ) ln ± ( Ψ 5 )
= ln ± ( Ψ 7 ) + r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) D 27 ( 1 ) D 25 ( 1 ) D 25 ( 2 ) D 23 ( 1 ) D 23 ( 2 ) + D 23 ( 3 ) r D 77 ( 1 ) ( D 57 ( 1 ) ) ϕ ( D 37 ( 1 ) ) ϕ D 57 ( 1 ) D 55 ( 1 ) D 55 ( 2 ) ( D 35 ( 1 ) D 35 ( 2 ) ) ϕ D 37 ( 1 ) D 35 ( 1 ) D 35 ( 2 ) D 33 ( 1 ) D 33 ( 2 ) + D 33 ( 3 ) D 17 ( 1 ) D 15 ( 1 ) D 15 ( 2 ) D 13 ( 1 ) D 13 ( 2 ) + D 13 ( 3 ) .
According to Step 3 (1) and Step 3 (2), the results in the paper (Step 3) can be obtained.

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Yu, S.-W.; Zhang, X.-N.; Qin, W.-L.; He, Z.-H. Some Properties of the Solution to a System of Quaternion Matrix Equations. Axioms 2022, 11, 710. https://doi.org/10.3390/axioms11120710

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Yu S-W, Zhang X-N, Qin W-L, He Z-H. Some Properties of the Solution to a System of Quaternion Matrix Equations. Axioms. 2022; 11(12):710. https://doi.org/10.3390/axioms11120710

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Yu, Shao-Wen, Xiao-Na Zhang, Wei-Lu Qin, and Zhuo-Heng He. 2022. "Some Properties of the Solution to a System of Quaternion Matrix Equations" Axioms 11, no. 12: 710. https://doi.org/10.3390/axioms11120710

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Yu, S. -W., Zhang, X. -N., Qin, W. -L., & He, Z. -H. (2022). Some Properties of the Solution to a System of Quaternion Matrix Equations. Axioms, 11(12), 710. https://doi.org/10.3390/axioms11120710

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