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arXiv · 1709.05194

On a conjecture of Faulhuber and Steinerberger on the logarithmic derivative of $\vartheta_4$

Anne-Maria Ernvall-Hytönen·Esa V. Vesalainen
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Abstract

Faulhuber and Steinerberger conjectured that the logarithmic derivative of $\vartheta_4$ has the property that $y^2\,\vartheta_4'(y)/\vartheta_4(y)$ is strictly decreasing and strictly convex. In this small note, we prove this conjecture.

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Anne-Maria Ernvall-Hytönen, Esa V. Vesalainen. 2017-09-15. On a conjecture of Faulhuber and Steinerberger on the logarithmic derivative of $\vartheta_4$. https://arxiv.org/abs/1709.05194

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