English

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

Commutative Algebra 2014-09-08 v2

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.

Cite

@article{arxiv.1405.6809,
  title  = {Squarefree monomial ideals that fail the persistence property and non-increasing depth},
  author = {Huy Tai Ha and Mengyao Sun},
  journal= {arXiv preprint arXiv:1405.6809},
  year   = {2014}
}

Comments

14 pp; minor revision; to appear in Acta Mathematica Vietnamica

R2 v1 2026-06-22T04:23:55.535Z