A Search For Solvable Weighing Matrices: supporting documents

This file contains additional information relating to the article: “A Search for Solvable Weighing Matrices,” submitted to Journal of Combinatorial Mathematics and Combinatorial Computing Feb. 25, 2005. In that article, we describe a computer search for group-developed weighing matrices of order 60 and weight 25, which we abbreviate as W (60, 25). Generally speaking, we view weighing matrices as polynomials in a rational group ring QG. We restrict the search space for these polynomials by correlating projections into quotient group rings Q(G/N) for various normal subgroups, N . We call the projection of a weighing matrix polynomial into Q(G/N) a G/N quotient image. Due to restrictions on space, the submitted article leaves out many details of the computation of small quotient images. That information is included in this file, along with relevant information about the structure of groups of order 60.