COLLECTION FROM THE LEFT

The heart of the nilpotent quotient algorithm for computing in finite p-groups is a collection algorithm for collecting semigroup words on the generators of the group into normal form. In applications of the nilpotent quotient algorithm almost all the computing time is spent doing collections, and so very sophisticated collection algorithms have been developed. A number of researchers recently have started investigating a variant of the algorithm known as collection from the left. A version of collection from the left is described in this article. It is designed as an alternative to the Havas-Nicholson algorthm for collection from the right which is incorporated in the Canberra version of the nilpotent quotient algorithm. Indications are that for many applications it runs faster than the Havas-Nicholson algorithm