Dear Forum Members, I am very pleased to announce that the GAP package Congruence (version 1.1.1) has been officially accepted as a package for GAP, and is included in the latest GAP 4.7.6 release. The package is authored by Ann Dooms, Eric Jespers, Alexander Konovalov and Helena Verrill, and is maintained by Alexander Konovalov. On behalf of the GAP Council I wish to thank the authors for this contribution to GAP.
The Congruence package provides functions for constructing several types of canonical congruence subgroups in SL_2(Z), as well as intersections of a finite number of such subgroups. Furthermore, it implements the algorithm for generating Farey symbols for congruence subgroups and using them to produce a system of independent generators for these subgroups The Congruence package can be downloaded from its GAP webpage http://www.gap-system.org/Packages/congruence.html where PDF documentation is available. All the best, Graham School of Mathematics, Statistics & Applied Mathematics National University of Ireland, Galway University Road, Galway Ireland http://hamilton.nuigalway.ie tel: 091 493011 _______________________________________________ Forum mailing list Forum@mail.gap-system.org http://mail.gap-system.org/mailman/listinfo/forum
