FGA - Free Group Algorithms

A GAP 4 package

Contents:

The FGA package provides methods for computations with finitely generated subgroups of free groups.

It allows you to (constructively) test membership and conjugacy, and to compute free generators, the rank, the index, normalizers, centralizers, and intersections where the groups involved are finitely generated subgroups of free groups.

In addition, it provides generators and a finite presentation for the automorphism group of a finitely generated free group and allows to write any such automorphism as word in these generators.

Note that this version of FGA is a fork of the original FGA package by Christian Sievers, available at https://github.com/chsievers/fga. This fork is maintained by the GAP team to incorporate various minor changes.

Requirements:

FGA is written for GAP version 4.8 or later. It does not use external programs and does not depend on system specifics.

License:

The FGA package is free software and can be redistributed and/or modified under the terms of the GNU General Public License; either version 2 of the License, or (at your option) any later version. For details see the file COPYING.

Installation:

The installation follows standard GAP rules. So the normal way to install is to unpack the archive in the pkg directory, which will create an fga subdirectory.

Enjoy!