How to Read the Decomposition Matrices

For a fixed characteristic p and a fixed simple group G, various bicyclic extensions m.G.a may occur, where G.a is a subgroup of the automorphism group of G and m is a cyclic factor of the Schur multiplier of G.a. For each such group G.a, the information about all bicyclic extensions m.G.a that occur in the ATLAS of Finite Groups is shown together in one document. Each file starts with the name of the group G.a and the characteristic p, followed by an overview of the blocks. Finally, the decomposition matrices themselves are listed blockwise.