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arXiv · 1904.05733

The Hochschild cohomology ring of the numerical semigroup algebras of embedding dimension two

Nghia T. H. Tran·Emil Sköldberg
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Abstract

Let $a$ and $b$ be two coprime positive integers and $k$ an arbitrary field. We determine the ring structure of the Hochschild cohomology of the numerical semigroup algebras $k[s^{a},s^{b}]$ of embedding dimension two (thus also complete intersections) in terms of generators and relations. In addition, we compute the Hilbert series for this cohomology ring.

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Nghia T. H. Tran, Emil Sköldberg. 2019-04-11. The Hochschild cohomology ring of the numerical semigroup algebras of embedding dimension two. https://arxiv.org/abs/1904.05733

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