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arXiv · 1010.1197

Hamming graphs in Nomura Algebras

Ada Chan·Akihiro Munemasa
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Abstract

Let A be an association scheme on q\geq 3 vertices. We show that the Bose-Mesner algebra of the generalized Hamming scheme H(n,A), for n\geq 2, is not the Nomura algebra of a type II matrix. This result gives examples of formally self-dual Bose-Mesner algebras that are not the Nomura algebras of type II matrices.

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Ada Chan, Akihiro Munemasa. 2011-01-13. Hamming graphs in Nomura Algebras. https://arxiv.org/abs/1010.1197

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