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arXiv · 2302.14675

Flat semigroups and weighted homogeneous surface singularities

Zsolt Baja·Tamás László
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Abstract

We consider numerical semigroups associated with normal weighted homogeneous surface singularities with rational homology sphere links. We say that a semigroup is representable if it can be realized in this way. In this article, we study the representability of flat semigroups and prove that a numerical semigroup is representable if and only if it can be written as a quotient of a flat semigroup.

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Zsolt Baja, Tamás László. 2023-02-28. Flat semigroups and weighted homogeneous surface singularities. https://doi.org/10.2140/agt.2026.26.201

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