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arXiv · 1904.10201

Graded rings of paramodular forms of levels $5$ and $7$

Brandon Williams
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Abstract

We compute generators and relations for the graded rings of paramodular forms of degree two and levels 5 and 7. The generators are expressed as quotients of Gritsenko lifts and Borcherds products. The computation is made possible by a characterization of modular forms on the Humbert surfaces of discriminant 4 that arise from paramodular forms by restriction.

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Brandon Williams. 2020-03-16. Graded rings of paramodular forms of levels $5$ and $7$. https://arxiv.org/abs/1904.10201

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