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arXiv · 1405.6809

Squarefree monomial ideals that fail the persistence property and non-increasing depth

Huy Tai Ha·Mengyao Sun
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Abstract

In a recent work, Kaiser, Stehl\'ik and \v{S}krekovski provide a family of critically 3-chromatic graphs whose expansions do not result in critically 4-chromatic graphs, and thus give counterexamples to a conjecture of Francisco, Ha and Van Tuyl. The cover ideal of the smallest member of this family also gives a counterexample to the persistence and non-increasing depth properties. In this paper, we show that the cover ideals of all members of their family of graphs indeed fail to have the persistence and non-increasing depth properties.

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Huy Tai Ha, Mengyao Sun. 2014-05-27. Squarefree monomial ideals that fail the persistence property and non-increasing depth. https://arxiv.org/abs/1405.6809

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