Self-dual codes over [formula omitted] with an automorphism of odd order

Abstract

We complete the classification of all Lee-extremal and Lee-optimal self-dual codes over F 2 + u F 2 of lengths 9 through 20 that have a nontrivial odd order automorphism begun in [W.C. Huffman, On the decomposition of self-dual codes over F 2 + u F 2 with an automorphism of odd prime order, Finite Fields Appl., in press]. Along the way, we find all Lee-extremal self-dual codes over F 2 + u F 2 of lengths 9 through 11.