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arXiv · 2007.03998

The automorphism group of the modular curve $X_0^*(N)$ with square-free level

Francesc Bars·Josep González
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Abstract

We determine the automorphism group of the modular curve $X_0^*(N)$, obtained as the quotient of the modular curve $X_0(N)$ by the group of its Atkin-Lehner involutions, for all square-free values of $N$.

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Francesc Bars, Josep González. 2020-07-08. The automorphism group of the modular curve $X_0^*(N)$ with square-free level. https://arxiv.org/abs/2007.03998

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