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arXiv · 2008.13322

Graded rings of modular forms (1)

Suda Tomohiko
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Abstract

We study modular forms of some congruence subgroups. In this paper, we treat the cases level is 2-power, 3-power or 5. Structures of graded rings and many identities of infinite sum or infinite product are given. Theory of rational (1/3, 1/4, 1/5 etc) weight or more formally weight modular form are introduced.

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Suda Tomohiko. 2020-08-31. Graded rings of modular forms (1). https://arxiv.org/abs/2008.13322

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