The unbounded denominator conjecture for the noncongruence subgroups of index 7

2020/07/02 by Fiori, Andrew, Franc, Cameron
#FOS: Mathematics #Number Theory (math.NT)

paper · doi:10.48550/arxiv.2007.01336

Abstract

We study modular forms for the minimal index noncongruence subgroups of the modular group. Our main theorem is a proof of the unbounded denominator conjecture for these groups, and we also provide a study of the Fourier coefficients of Eisenstein series for one of these minimal groups.

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