Hadamard matrices of order ≡8 (mod 16) with maximal excess
نویسندگان
چکیده
منابع مشابه
Hadamard matrices of order =8 (mod 16) with maximal excess
Kounias and Farmakis, in 'On the excess of Hadamard matrices', Discrete Math. 68 (1988) 59-69, showed that the maximal excess (or sum of the elements) of an Hadamard matrix of order h, o(h) for h = 4m(m -1) is given by o(4m(m 1))≤4(m 1)2(2m + 1). Kharaghani in 'An infinite class of Hadamard matrices of maximal excess' (to appear) showed this maximal excess can be attained if m is the order of a...
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A complex Hadamard matrix, C, of order n has elements 1, -1, i, i and satisfies CC* = nIn where C* denotes the conjugate transpose of C. Let C = [cij] be a complex Hadamard matrix of order n. S(C) = ∑ cij is called the sum of C. 0(C) = │S(C)│ is called the excess of C. We study the excess of complex Hadamard matrices. As an application many real Hadamard matrices of large and maximal excess are...
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متن کاملConstruction of some Hadamard matrices with maximum excess
o(n) = max a(H) for all H-matrices of order n (1) An equivalent notion is the weight w(H) which is the number of l’s in H, then a(H) = 2w(H) n2 and u(n) = 2w(n) n2, see [4,12,15]. H-matrices with maximum excess are known for the following values of n: n 6 52 (n = 0 mod 4), n = 64, 80, 84, 100, 124, 144, 172, 196, 256, 324, 400, and IZ = (4m)*, where 4m is the order of an H-matrix [2,4-5,10-12,1...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1991
ISSN: 0012-365X
DOI: 10.1016/0012-365x(91)90278-a