A method for constructing inequivalent self-dual codes with applications to length 56
IEEE Transactions on Information Theory
The binary self-dual codes of length up to 32: a revised enumeration
Journal of Combinatorial Theory Series A
On the nonexsitence of extremal self-dual codes
Discrete Applied Mathematics
Handbook of Coding Theory
Self-dual extended cyclic codes
Applicable Algebra in Engineering, Communication and Computing
On binary self-dual codes of lengths 60, 62, 64 and 66 having an automorphism of order 9
Designs, Codes and Cryptography
Shadow bounds for self-dual codes
IEEE Transactions on Information Theory
New extremal self-dual codes of length 62 and related extremal self-dual codes
IEEE Transactions on Information Theory
A note on self-dual group codes
IEEE Transactions on Information Theory
On the structure of binary self-dual codes having an automorphism of order a square of an odd prime
IEEE Transactions on Information Theory
On the Classification of Extremal Binary Self-Dual Codes
IEEE Transactions on Information Theory
Classification of the binary self-dual [42,21,8] codes having an automorphism of order 3
Finite Fields and Their Applications
On the classification and enumeration of self-dual codes
Finite Fields and Their Applications
Designs, Codes and Cryptography
| Hi-index | 754.84 |
Let C be a binary extremal self-dual code of length n ≥ 48. We prove that for each σ ∈ Aut(C) of prime order p ≥ 5 the number of fixed points in the permutation action on the coordinate positions is bounded by the number of p-cycles. It turns out that large primes p, i.e., n - p small, seem to occur in |Aut(C)| very rarely. Examples are the extended quadratic residue codes. We further prove that doubly even extended quadratic residue codes of length n = p + 1 are extremal only in the cases n = 8, 24, 32, 48, 80, and 104.