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On Zeros of Some Entire Functions

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Abstract

Let

$$\begin{aligned} A_{q}^{(\alpha )}(a;z)=\sum _{k=0}^{\infty }\frac{(a;q)_{k}q^{\alpha k^2} z^k}{(q;q)_{k}}, \end{aligned}$$

where \(\alpha >0,~0<q<1.\) In a paper of Ruiming Zhang, he asked under what conditions the zeros of the entire function \(A_{q}^{(\alpha )}(a;z)\) are all real and established some results on the zeros of \(A_{q}^{(\alpha )}(a;z)\) which present a partial answer to that question. In the present paper, we will set up some results on certain entire functions which includes that \(A_{q}^{(\alpha )}(q^l;z),~l\ge 2\) has only infinitely many negative zeros that gives a partial answer to Zhang’s question. In addition, we establish some results on zeros of certain entire functions involving the Rogers–Szegő polynomials and the Stieltjes–Wigert polynomials.

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Acknowledgements

This work was partially supported by the National Natural Science Foundation of China (Grant No. 11801451).

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Correspondence to Bing He.

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He, B. On Zeros of Some Entire Functions. Results Math 74, 52 (2019). https://doi.org/10.1007/s00025-019-0978-y

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