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Group properties of Hadamard matrices

Published online by Cambridge University Press:  09 April 2009

Marshall Hall Jr
Affiliation:
Department of MathematicsCalifornia Institute of Technology Pasadena, California, U.S.A.
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An Hadamard matrix H is a square matrix of order n all of whose entries are ± 1 such thatThere are matrices of order 1 and 2and for all other Hadamard matrices the order n is a multiple of 4, n = 4m. It is a reasonable conjecture that Hadamard matrices exist for every order which is a multiple of 4 and the lowest order in doubt is 268. With every Hadamard matrix H4m a symmetric design D exists with

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1976

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