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arXiv · 0801.4693

A Modular Curve of Level 9 and the Class Number One Problem

Burcu Baran
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Abstract

In this note we give an explicit parametrization of the modular curve associated to the normalizer of a non-split Cartan subgroup of level 9. We determine all integral points of this modular curve. As an application, we give an alternative solution to the class number one problem.

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Burcu Baran. 2009-02-18. A Modular Curve of Level 9 and the Class Number One Problem. https://doi.org/10.1016/j.jnt.2008.09.013

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