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arXiv · 2006.01470

Combinatoire des sous-groupes de congruence du groupe modulaire

Flavien Mabilat
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Abstract

In this paper, we study the combinatorics of congruence subgroups of the modular group by generalizing results obtained in the non-modular case. For this, we define a notion of irreducible solutions from which we can build all the solutions. In particular, we give a particular solution, irreducible for any $N$, and the list of irreducible solutions for $N \leq 6$.

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Flavien Mabilat. 2021-12-07. Combinatoire des sous-groupes de congruence du groupe modulaire. https://arxiv.org/abs/2006.01470

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