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arXiv · 1111.1433

On the Betti numbers of some semigroup rings

Vincenzo Micale·Anda Olteanu
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Abstract

For any numerical semigroup $S$, there are infinitely many numerical symmetric semigroups $T$ such that $S=\frac{T}{2}$ is their half. We are studying the Betti numbers of the numerical semigroup ring $K[T]$ when $S$ is a 3-generated numerical semigroup or telescopic. We also consider 4-generated symmetric semigroups and the so called 4-irreducible numerical semigroups.

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Vincenzo Micale, Anda Olteanu. 2011-11-06. On the Betti numbers of some semigroup rings. https://arxiv.org/abs/1111.1433

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