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arXiv · 1802.02000

Finite subgroups of the extended modular group

Gregory Dresden·Prakriti Panthi·Anukriti Shrestha·Jiahao Zhang
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Abstract

We show that in the extended modular group PGL(2,Z) there are exactly seven finite subgroups up to conjugacy; three subgroups of size 2, one subgroup each of size 3, 4, and 6, and the trivial subgroup of size 1.

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Gregory Dresden, Prakriti Panthi, Anukriti Shrestha, Jiahao Zhang. 2018-02-06. Finite subgroups of the extended modular group. https://arxiv.org/abs/1802.02000

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