Finding normal subgroups of low index in finitely-presented groups
by
Marston Conder
Mathematics Department, University of Auckland
Coauthors: Peter Dobcsanyi

An effective computational algorithm (due to Charles Sims) exists for finding subgroups of up to a given index in a finitely-presented group G = <X | R >, and this has been used fruitfully in several contexts. A recent adaptation of the algorithm finds only normal subgroups, and runs much faster, or up to much larger index. This adaptation will be described briefly along with some significant applications - for example to the classification of regular maps of genus up to 12, and all trivalent symmetric graphs on up to 500 vertices.

Date received: April 16, 1999