The existence of an extremal code of length 72 is a long-standing open problem. Let C be a putative extremal code of length 72 and suppose that C has an automorphism g of order 6. We show that C, as an BBF2 〈g〉-module, is the direct sum of two modules; it is easy to determine one of them, while the other one has a very restrictive structure. We use this fact to do an exhaustive search and we do not find an extremal code. This proves that the automorphism group of an extremal code of length 72 does not contain elements of order 6
Borello, M. (2012). The Automorphism Group of a Self-Dual [72, 36, 16] Binary Code Does Not Contain Elements of Order 6. IEEE TRANSACTIONS ON INFORMATION THEORY, 58(12), 7240-7245 [10.1109/TIT.2012.2211095].
The Automorphism Group of a Self-Dual [72, 36, 16] Binary Code Does Not Contain Elements of Order 6
BORELLO, MARTINO
2012
Abstract
The existence of an extremal code of length 72 is a long-standing open problem. Let C be a putative extremal code of length 72 and suppose that C has an automorphism g of order 6. We show that C, as an BBF2 〈g〉-module, is the direct sum of two modules; it is easy to determine one of them, while the other one has a very restrictive structure. We use this fact to do an exhaustive search and we do not find an extremal code. This proves that the automorphism group of an extremal code of length 72 does not contain elements of order 6I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.