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arXiv · 2403.14299

Cohen-Macaulayness of vertex splittable monomial ideals

Marilena Crupi·Antonino Ficarra
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Abstract

In this paper, we give a new criterion for the Cohen-Macaulayness of vertex splittable ideals, a family of monomial ideals recently introduced by Moradi and Khosh-Ahang. Our result relies on a Betti splitting of the ideal and provides an inductive way of checking the Cohen-Macaulay property. As a result, we obtain characterizations for Gorenstein, level and pseudo-Gorenstein vertex splittable ideals. Furthermore, we provide new and simpler combinatorial proofs of known Cohen-Macaulay criteria for several families of monomial ideals, such as (vector-spread) strongly stable ideals and (componentwise) polymatroidals. Finally, we characterize the family of bi-Cohen-Macaulay graphs by the novel criterion for the Cohen-Macaulayness of vertex splittable ideals.

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Marilena Crupi, Antonino Ficarra. 2024-03-21. Cohen-Macaulayness of vertex splittable monomial ideals. https://doi.org/10.3390/math12060912

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