Extremal doubly even (56, 28, 12) codes and Hadamard matrices of order 28
نویسنده
چکیده
In [2] Bussemaker and Tonchev constructed six doubly even (56,28, 12) codes from two Hadamard matrices of order 28. But two of them were not distinguished. In [11] and [12] we characterized Hadamard matrices of order 28 and there are exactly 487 Hadamard matrices, up to equivalence. In this paper we show that only two of the above 487 matrices produce six doubly even (56,28,12) codes and that two of the six codes are equivalent. Therefore there are exactly five (56,28,12) codes, up to equivalence, produced by Hadamard matrices of order 28.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 10 شماره
صفحات -
تاریخ انتشار 1994