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arXiv · 2109.11858

An asymptotic expansion for a twisted Lambert series associated to a cusp form and the Möbius function: level aspect

Bibekananda Maji·Sumukha Sathyanarayana·B. R. Shankar
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Abstract

Recently, Juyal, Maji, and Sathyanarayana have studied a Lambert series associated with a cusp form over the full modular group and the Möbius function. In this paper, we investigate the Lambert series $\sum_{n=1}^{\infty}[a_f(n)ψ(n)*μ(n)ψ'(n)]\exp(-ny),$ where $a_f(n)$ is the $n$th Fourier coefficient of a cusp form $f$ over any congruence subgroup, and $ψ$ and $ ψ'$ are primitive Dirichlet characters. This extends the earlier work to the case of higher level subgroups and also gives a character analogue.

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Bibekananda Maji, Sumukha Sathyanarayana, B. R. Shankar. 2021-09-24. An asymptotic expansion for a twisted Lambert series associated to a cusp form and the Möbius function: level aspect. https://arxiv.org/abs/2109.11858

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