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Symmetric Conference Matrices of Order pq2 + 1

Published online by Cambridge University Press:  20 November 2018

Rudolf Mathon*
Affiliation:
University of Toronto Toronto, Ontario
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A conference matrix of order n is a square matrix C with zeros on the diagonal and ±1 elsewhere, which satisfies the orthogonality condition CCT = (n — 1)I. If in addition C is symmetric, C =CT, then its order n is congruent to 2 modulo 4 (see [5]). Symmetric conference matrices (C) are related to several important combinatorial configurations such as regular two-graphs, equiangular lines, Hadamard matrices and balanced incomplete block designs [1; 5; and 7, pp. 293-400]. We shall require several definitions.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1978

References

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