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Non-commutative duplicates of finite sets

Claude Cibils
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Abstract

We classify the twisted tensor products of a finite set algebra with a two elements set algebra using colored quivers obtained through considerations analogous to Ore extensions. This provides also a classification of entwining structures between a finite set algebra and the grouplike coalgebra on two elements. The resulting 2-nilpotent algebras have particular features with respect to Hochschild (co)homology and cyclic homology.

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Claude Cibils. 2005-04-05. Non-commutative duplicates of finite sets. https://arxiv.org/abs/math/0405593

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