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arXiv · 2007.01336

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

Andrew Fiori·Cameron Franc
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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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BibTeXRIS

Andrew Fiori, Cameron Franc. 2020-07-10. The unbounded denominator conjecture for the noncongruence subgroups of index $7$. https://arxiv.org/abs/2007.01336

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