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arXiv · 2410.12571

A unified approach to Rohrlich-type divisor sums

Daeyeol Jeon·Soon-Yi Kang·Chang Heon Kim·Toshiki Matsusaka
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Abstract

We propose a systematic method for analyzing Rohrlich-type divisor sums for arbitrary congruence subgroups $\Gamma_0(N)$. Our main theorem unifies various results from the literature, and its significance is illustrated through the following five applications: (1) the valence formula, (2) a natural generalization of classical Rohrlich's formula to level $N$, (3) an explicit version of the theorem by Bringmann-Kane-L\"{o}brich-Ono-Rolen, (4) an extension of the generalized Rohrlich formula proposed by Bringmann-Kane, and (5) an alternative proof of the decomposition formula for twisted traces of CM values of weight 0 Eisenstein series.

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Daeyeol Jeon, Soon-Yi Kang, Chang Heon Kim, Toshiki Matsusaka. 2024-10-16. A unified approach to Rohrlich-type divisor sums. https://arxiv.org/abs/2410.12571

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