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arXiv · 2603.09572

A complex Hadamard matrix of order 94

Ferenc Szöllősi
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Abstract

In this paper we modify a fundamental block construction of Kharaghani and Seberry and show how to use certain circulant $\{-1,1\}$-matrices of odd order $p$ to construct a complex Hadamard matrix of order $2p$. In particular, for $p=47$ we use computer-aided methods to discover the necessary circulant matrices, and consequently give a construction of a complex Hadamard matrix of order $94$ for the first time.

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Ferenc Szöllősi. 2026-03-10. A complex Hadamard matrix of order 94. https://arxiv.org/abs/2603.09572

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