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An infinite class of Hadamard matrices of maximal excess. (English) Zbl 0734.05028
Let H be an Hadamard matrix of order n. Then \(\sigma\) (H) denotes the sum of all entries of H. Furthermore \[ \sigma (n)=_{H} \sigma (H), \] where H runs over all Hadamard matrices of order n. Now the main result of the present paper is the following theorem: If m is the order of a skew Hadamard matrix, then \[ \sigma (4m^ 2-4m)=4(m-1)^ 2(2m+1). \]

05B20 Combinatorial aspects of matrices (incidence, Hadamard, etc.)
Hadamard matrix
Full Text: DOI
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