English

Graded rings of modular forms (1)

Number Theory 2020-09-01 v1

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.

Keywords

Cite

@article{arxiv.2008.13322,
  title  = {Graded rings of modular forms (1)},
  author = {Suda Tomohiko},
  journal= {arXiv preprint arXiv:2008.13322},
  year   = {2020}
}

Comments

Keywords: Modular form, Rational weight, Graded ring

R2 v1 2026-06-23T18:11:52.033Z