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arXiv · 2205.05349

Reconstructing a generalized quadrangle with a hemisystem from a $4-$class association scheme

Giusy Monzillo
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Abstract

In 2013, van Dam, Martin and Muzychuk constructed a cometric $Q-$ antipodal $4-$class association scheme from a GQ of order $(t^2,t)$, $t$ odd, which have a hemisystem. In this paper we characterize this scheme by its Krein array. The techniques which are used involve the triple intersection numbers introduced by Coolsaet and Jurišić.

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Giusy Monzillo. 2022-05-11. Reconstructing a generalized quadrangle with a hemisystem from a $4-$class association scheme. https://arxiv.org/abs/2205.05349

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