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arXiv · 1008.4766

Class number formulas via 2-isogenies of elliptic curves

Cam McLeman·Christopher Rasmussen
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Abstract

A classical result of Dirichlet shows that certain elementary character sums compute class numbers of quadratic imaginary number fields. We obtain analogous relations between class numbers and a weighted character sum associated to a 2-isogeny of elliptic curves.

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Cam McLeman, Christopher Rasmussen. 2012-04-02. Class number formulas via 2-isogenies of elliptic curves. https://doi.org/10.1112/blms%2Fbds049

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