On the spectrum of a partial theta function

Vladimir Petrov Kostov

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arXiv · 1504.00885

On the spectrum of a partial theta function

Vladimir Petrov Kostov

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Abstract

The bivariate series $\theta (q,x):=\sum_{j=0}^{\infty}q^{j(j+1)/2}x^j$ defines a {\em partial theta function}. For fixed $q$, $\theta (q,.)$ is an entire function. We show that for $|q|\leq 0.108$ the function $\theta (q,.)$ has no multiple zeros.

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Vladimir Petrov Kostov. 2015-04-03. On the spectrum of a partial theta function. https://arxiv.org/abs/1504.00885

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