This package provides an algorithm that computes a subgroup ladder from a permutation group up to the parent symmetric group. There is also a function included which computes portions of the table of marks using subgroup chains. The authors hope that this will someday be extended to use arbitrary subgroup ladders.
The documentation of this package is available as HTML and as a PDF.
It can also be generated locally with gap makedoc.g.
You can report issues on GitHub at https://github.com/ehwat/subgroupladders.
subgroupladders is free software you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. For details, see the file LICENSE distributed as part of this package or see the FSF's own site.