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arXiv · 0906.0911

Tangent cones of numerical semigroup rings

Teresa Cortadellas Benitez·Santiago Zarzuela Armengou
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Abstract

In this paper we describe the structure of the tangent cone of a numerical semigroup ring $A=k[[S]] \subseteq k[[t]]$ with multiplicity $e$ (as a module over the Noether normalization determined by the fiber cone of the ideal generated by $t^e$) in terms of some classical invariants of the corresponding numerical semigroup. Explicit computations are also made by using the GAP system.

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Teresa Cortadellas Benitez, Santiago Zarzuela Armengou. 2009-06-04. Tangent cones of numerical semigroup rings. https://arxiv.org/abs/0906.0911

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