# ORTHOGONAL MATRICES WITH ZERO DIAGONAL

@article{Goethals1967ORTHOGONALMW, title={ORTHOGONAL MATRICES WITH ZERO DIAGONAL}, author={Jean-Marie Goethals and J. J. Seidel}, journal={Canadian Journal of Mathematics}, year={1967}, volume={19}, pages={1001-1010} }

1. Introduction. C-matrices appear in the literature at various places; for a survey, see [11]. Important for the construction of Hadamard matrices are the symmetric C-matrices, of order v = 2 (mod 4), and the skew C-matrices, of order v = 0 (mod 4). In § 2 of the present paper it is shown that there are essentially no other C-matrices. A more general class of matrices with zero diagonal is investigated, which contains the C-matrices and the matrices of (v, k, X)-systems on k and k + 1 in the… Expand

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