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arXiv · 0706.1973

Skew-Hadamard matrices of orders 436, 580 and 988 exist

Dragomir Z. Djokovic
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Abstract

We construct two difference families on each of the cyclic groups of order 109, 145 and 247, and use them to construct skew-Hadamard matrices of orders 436, 580 and 988. Such difference families and matrices are constructed here for the first time. The matrices are constructed by using the Goethals-Seidel array.

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Dragomir Z. Djokovic. 2007-06-13. Skew-Hadamard matrices of orders 436, 580 and 988 exist. https://arxiv.org/abs/0706.1973

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