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arXiv · 0809.0020

On modular forms for some noncongruence subgroups of SL_2(Z) II

Ling Long·Chris Kurth
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Abstract

In this paper we show two classes of noncongruence subgroups satisfy the so-called unbounded denominator property. In particular, we establish our conjecture in [KL08] which says that every type II noncongruence character group of Gamma^0(11) satisfies the unbounded denominator property.

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Ling Long, Chris Kurth. 2008-08-29. On modular forms for some noncongruence subgroups of SL_2(Z) II. https://doi.org/10.1112/blms%2Fbdp061

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