m at h . C O ] 1 4 M ay 2 01 3 Some new orders of Hadamard and Skew - Hadamard matrices
نویسندگان
چکیده
We construct Hadamard matrices of orders 4 · 251 = 1004 and 4 · 631 = 2524, and skewHadamard matrices of orders 4 · 213 = 852 and 4 · 631 = 2524. As far as we know, such matrices have not been constructed previously. The constructions use the GoethalsSeidel array, suitable supplementary difference sets on a cyclic group and a new efficient matching algorithm based on hashing techniques.
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