The unbounded denominator conjecture for the noncongruence subgroups of index $7$

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.

References in corpus (1)

• On scattering constants for a non-congruence subgroup