Arithmetic Subgroups of ${\rm SL}_2({\bf Z})$

This chapter describes the basic functionality for finite index subgroups of the modular group ${\rm SL}_2(\ZZ)$.

• Arithmetic subgroups (finite index subgroups of ${\rm SL}_2(\ZZ)$)
• Arithmetic subgroups defined by permutations of cosets
• Elements of Arithmetic Subgroups
• Congruence arithmetic subgroups of ${\rm SL}_2(\ZZ)$
• Congruence Subgroup $\Gamma_H(N)$
• Congruence Subgroup $\Gamma_1(N)$
• Congruence Subgroup $\Gamma_0(N)$
• Congruence Subgroup $\Gamma(N)$
• The modular group ${\rm SL}_2(\ZZ)$
• Farey Symbol for arithmetic subgroups of ${\rm PSL}_2(\ZZ)$
• Cython helper functions for congruence subgroups

Indices and Tables

• Index
• Module Index
• Search Page