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arXiv · 2604.21157

Relations between higher level Hurwitz class numbers

Ngoc Trinh Le
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Abstract

We connect generalizations of the classical Hurwitz class numbers coming from two different frameworks: one introduced by Pei and Wang, arising from the generalized Cohen--Eisenstein series, and another by Li, Skoruppa, and Zhou, arising from Eichler orders of quaternion algebras. As applications, we obtain new basis for Eisenstein space $E_{3/2}^{+}(4N,\mathrm{id})$, a generalization of recent results of Beckwith and Mono, and a generalization of Gauss' formula.

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Ngoc Trinh Le. 2026-04-22. Relations between higher level Hurwitz class numbers. https://arxiv.org/abs/2604.21157

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