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Article
On integer matrices obeying certain matrix equations
Faculty of Informatics - Papers (Archive)
Publication Date
1-1-1972
Abstract
We discuss integer matrices B of odd order v which satisfy
Br = ± B, BBr = vI - J, BJ = O.
Matrices of this kind which have zero diagonal and other elements ± 1 give rise to skew-Hadamard and n-type matrices; we show that the existence of a skew-Hadamard (n-type) matrix of order h implies the existence of skew-Hadamard (n-type) matrices of orders (h - 1)5 + 1 and (h - 1)7 + 1. Finally we show that, although there are matrices B with elements other than ± 1 and 0, the equations force considerable restrictions on the elements of B.
Disciplines
Citation Information
Jennifer Seberry. "On integer matrices obeying certain matrix equations" (1972) Available at: http://works.bepress.com/jseberry/337/
Jennifer Seberry Wallis, On integer matrices obeying certain matrix equations, Journal of Combinatorial Theory, Ser. A., 12, (1972), 112-118.