# CONSTRUCTIONS FOR SPARSE ROW-ORTHOGONAL MATRICES WITH A FULL ROW

• Published : 1999.03.01

#### Abstract

In [4], it was shown that an n by n orthogonal matrix which has a row of nonzeros has at least ( log2n + 3)n - log2n +1 nonzero entries. In this paper, the matrices achieving these bounds are constructed. The analogous sparsity problem for m by n row-orthogonal matrices which have a row of nonzeros in conjectured.

#### References

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3. Rocky Mtn. Math. J. A simple proof of Fiedler's conjecture concerning orthogonal matrices B. L. Shader
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5. Discrete Applied Math. J. Sparse orthogonal matrices and the Haar wavelet G.-S. Cheon;B. L. Shader