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arXiv · 1604.02822

A combinatorial refinement of the Kronecker-Hurwitz class number relation

Alexandru A. Popa·Don Zagier
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Abstract

We give a refinement of the Kronecker-Hurwitz class number relation, based on a tesselation of the Euclidean plane into semi-infinite triangles labeled by $PSL_2(\mathbb{Z})$ that may be of independent interest.

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Alexandru A. Popa, Don Zagier. 2016-04-11. A combinatorial refinement of the Kronecker-Hurwitz class number relation. https://arxiv.org/abs/1604.02822

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