Self-dual Codes and Fixed-point-free Permutations of Order 2
نویسندگان
چکیده
We construct new binary optimal self-dual codes of length 50. We develop a construction method for binary self-dual codes with a fixed-point-free automorphism of order 2. Using this method, we find new binary optimal self-dual codes of length 52. From these codes, we obtain Lee-optimal self-dual codes over the ring F2 + uF2 of lengths 25 and 26.
منابع مشابه
Automorphism of order 2p in binary self-dual extremal codes of length a multiple of 24
Automorphisms of order 2p in binary self-dual extremal codes of length a multiple of 24 Abstract Let C be a binary self-dual code with an automorphism g of order 2p, where p is an odd prime, such that g p is a fixed point free involution. If C is extremal of length a multiple of 24 all the involutions are fixed point free, except the Golay Code and eventually putative codes of length 120. Conne...
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