Random generation of subgroups of the modular group with a fixed isomorphism type - Archive ouverte HAL
Journal Articles The Electronic Journal of Combinatorics Year : 2024

Random generation of subgroups of the modular group with a fixed isomorphism type

Abstract

We show how to efficiently count and generate uniformly at random finitely generated subgroups of the modular group PSL 2 (Z) of a given isomorphism type. The method to achieve these results relies on a natural map of independent interest, which associates with any finitely generated subgroup of PSL 2 (Z) a graph which we call its silhouette, and which can be interpreted as a conjugacy class of free finite index subgroups of PSL 2 (Z).
Fichier principal
Vignette du fichier
combi_silhouette.pdf (326.4 Ko) Télécharger le fichier
Origin Files produced by the author(s)

Dates and versions

hal-04695164 , version 1 (14-09-2024)

Identifiers

  • HAL Id : hal-04695164 , version 1

Cite

Frédérique Bassino, Cyril Nicaud, Pascal Weil. Random generation of subgroups of the modular group with a fixed isomorphism type. The Electronic Journal of Combinatorics, In press. ⟨hal-04695164⟩
28 View
8 Download

Share

More