1. Introduction
Hermite polynomials are classic orthogonal polynomials, and many studies have been conducted by various mathematicians. These Hermite polynomials also have many applications such as in physics and probability theory (see [
1,
2,
3,
4,
5,
6,
7,
8,
9,
10,
11]). Throughout this paper,
indicates the set of complex numbers and
designates a set of real numbers. Furthermore, the variable
, such that
.
q-analogues of
is specified as
Note that
The
q-Hermite polynomials
[
11,
12] are defined by
The differential equation and the generating function for
are given by
and
respectively.
Additionally, the polynomials
satisfy the following differential equation
Mathematicians have studied the differential equations arising from the generating functions of special numbers and polynomials (see [
12,
13,
14]). Based on the results so far, in this work, we can derive the differential equations generated from the generating function of degenerate
q-Hermite polynomials
. By using the coefficients of this differential equation, we obtain explicit identities for the degenerate
q-Hermite polynomials
The rest of the paper is organized as follows. In
Section 2, we derive the differential equations generated from the generating function of degenerate
q-Hermite polynomials
Using the coefficients of this differential equation, we obtain explicit identities for the degenerate
q-Hermite polynomials
In
Section 3, we use the software to check the zeros of the degenerate
q-Hermite equations. In addition, we observe the pattern of scattering phenomenon about the zeros of degenerate
q-Hermite equations.
2. Basic Properties for the Degenerate -Hermite Polynomials
In this section, we construct the degenerate q-Hermite polynomials . We obtain some properties of the degenerate q-Hermite polynomials .
Definition 1. The degenerate q-Hermite polynomials and degenerate q-Hermite numbers are usually defined by the generating functionsandrespectively. Clearly, .
Since
as
, it is evident that (2) reduces to (1). We recall that the classical Stirling numbers of the first kind
and the second kind
are defined by the relations
and
respectively (see [
15]). Here
denotes the falling factorial polynomial of order
n. We also have
We also need the binomial theorem: for a variable
x,
By comparing of the coefficients
on the both sides of (4), the following representation of
is obtained
and
denotes use of the integer part.
The following elementary properties of the degenerate q-Hermite polynomials are readily derived form (2). We, therefore, choose to omit the details involved.
Theorem 1. For any positive integer n, we havewhere denotes use of the integer part. Theorem 2. The degenerate q-Hermite polynomials in generating function (2) are the solution of the following equation: Proof. Substitute the series in (2) for
to obtain
This is the recurrence relation for degenerate
q-Hermite polynomials. Another recurrence relation comes from
Eliminate
from (6) and (7) to obtain
Differentiate this equation and use (6) and (7) again to obtain
Thus, we obtain the desired result. □
Another application of the differential equation for is as follows:
Theorem 3. The degenerate q-Hermite polynomials in generating function (2) are the solution of the following equation: Proof. Substitute the series in (8) for
to obtained
Differentiate this equation and use (8) and (9) again to derive
Therefore, the proof is complete. □
Recently, many mathematicians have studied differential equations that appeared based on the generative functions of special polynomials (see [
12,
13,
14]). In line with these studies, in this paper, we study the following: We obtain the differential equations generated using the generating function of Hermite polynomials:
We obtain some identities and properties for the degenerate
q-Hermite polynomials using the coefficients of this differential equation in
Section 3. In
Section 4, we find some figures to explore the zeros of the degenerate
q-Hermite equations using numerical methods.
3. Differential Equations Associated with Degenerate -Hermite Polynomials
Many researchers have studied differential equations arising from the generating functions of special polynomials, since they can find some useful identities and properties for special polynomials (see [
12,
13,
14]). In this section, we introduce differential equations using the generating functions of degenerate
q-Hermite polynomials. From these differential equations, we find some significant identities and properties for the degenerate
q-Hermite polynomials.
If we continue this process, we can make the following guess.
Differentiating (11) with respect to
t, we have
Now, replacing
N by
in (11), we find
Comparing the coefficients on both sides of (12) and (13), we obtain
and, for
,
In addition, by (11), we have
which gives
It is not difficult to show that
Thus, by (13), we also find
From (14), we note that
and
For
in (15), we have
Continuing this process, we can deduce that, for
Note that, here, the matrix
is given by
Therefore, by (14)–(24), we obtain the following theorem.
Theorem 4. For the differential equationhas a solutionwhere Theorem 5. For we havewhere Proof. Making
N-times derivative for (2) with respect to
t, we have
By (25) and (26), we have
Hence, we obtain the desired result. □
Corollary 1. For we havewhere Proof. If we take in Theorem 5, then we have the desired result. □
For
the differential equation
has a solution
This is a plot of the surface for this solution.
In
Figure 1 (left), we choose
and
In
Figure 1 (right), we choose
and
4. Zeros of the Degenerate -Hermite Polynomials
Recently, mathematicians have used software because it makes many concepts easier. These studies have allowed mathematicians to generate and visualize new ideas, to examine the properties of shapes, to create many conjectures. Based on this trend, we investigate the distribution and pattern of zeros of degenerate q-Hermite polynomials according to the change of degree n in this section.
First, a few examples of the specific polynomials of
defined in
Section 2 are shown below:
Using a computer, we investigate the distribution of zeros of the degenerate
q-Hermite polynomials
. Plots of the zeros of the degenerate
q-Hermite polynomials
for
and
are as follows (
Figure 2).
In the top-left picture of
Figure 2, we chose
and
. In the top-right picture of
Figure 2, we chose
and
. In the bottom-left picture of
Figure 2, we chose
and
. In the bottom-right picture of
Figure 2, we chose
and
.
Stacks of zeros of the degenerate
q-Hermite polynomials
for
from a 3-D structure are presented (
Figure 3).
In the left picture of
Figure 3, we chose
and
. In the right picture of
Figure 3, we chose
and
.
Our numerical results for approximate solutions of real zeros of the degenerate
q-Hermite polynomials
are displayed (
Table 1).
We can see a regular pattern of the complex roots of the degenerate
q-Hermite polynomials
and hope to verify the same kind of regular structure of the complex roots of the degenerate
q-Hermite polynomials
(
Table 1).
The plot of real zeros of the degenerate
q-Hermite polynomials
for
structure are presented (
Figure 4).
In the left picture of
Figure 4, we chose
. In the right picture of
Figure 4, we chose
.
Next, we calculated an approximate solution that satisfies
. The results are shown in
Table 2.
5. Conclusions
This paper focused on some explicit identities, recurrence relations and differential equations for c. Thus, we defined the degenerate q-Hermite polynomials in Definition 1 and obtained their formulas (Theorem 1), including explicit formulae (Theorem 5 and Corollary 1) and differential equations (Theorems 2–4). Finally, we examined the distribution and pattern of zeros of degenerate q-Hermite polynomials according to the change in degree n. We expect that research in this direction will be a new approach to using numerical methods for the study of degenerate q-Hermite polynomials .
Author Contributions
Conceptualization, C.-S.R.; methodology, C.-S.R.; formal analysis, J.-Y.K.; writing—original draft preparation, J.-Y.K. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no external funding.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
The data presented in this study are available on request from the corresponding author.
Conflicts of Interest
The authors declare no conflict of interest.
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