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arXiv · 2004.00926

Refined asymptotics of the Riemann-Siegel theta function

R. B. Paris
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Abstract

The Riemann-Siegel theta function $\vartheta(t)$ is examined for $t\to+\infty$. Use of the refined asymptotic expansion for $\log\,\g(z)$ shows that the expansion of $\vartheta(t)$ contains an infinite sequence of increasingly subdominant exponential terms, each multiplied by an asymptotic series involving inverse powers of $\pi t$. Numerical examples are given to detect and confirm the presence of the first three of these exponentials.

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R. B. Paris. 2020-04-02. Refined asymptotics of the Riemann-Siegel theta function. https://arxiv.org/abs/2004.00926

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