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arXiv · 1401.1700

A Corollary of Hamada and Ohmori's on Group Law over BIBD

Arnaud Bannier·Johann Barbier·Eric Filiol·Pierre Castel
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Abstract

In this note, we present an interesting corollary of a theorem of Hamada and Ohmori. We prove that the complementary of PG(n,2) is the only design, up to an isomorphism, whose blocks form a group for the symmetric difference.

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Arnaud Bannier, Johann Barbier, Eric Filiol, Pierre Castel. 2014-01-08. A Corollary of Hamada and Ohmori's on Group Law over BIBD. https://arxiv.org/abs/1401.1700

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