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arXiv · 1710.09298

Gluing semigroups and strongly indispensable free resolutions

Mesut Şahin·Leah Gold Stella
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Abstract

We study strong indispensability of minimal free resolutions of semigroup rings. We focus on two operations, gluing and extending, used in literature to produce more examples with a special property from the existing ones. We give a naive condition to determine whether gluing of two semigroup rings has a strongly indispensable minimal free resolution. As applications, we determine extensions of $3$-generated non-symmetric, $4$-generated symmetric and pseudo symmetric numerical semigroups as well as obtain infinitely many complete intersection semigroups of any embedding dimension, having strongly indispensable minimal free resolutions.

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Mesut Şahin, Leah Gold Stella. 2018-10-02. Gluing semigroups and strongly indispensable free resolutions. https://doi.org/10.1142/s0218196719500012

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