English

Gapfree graphs and powers of edge ideals with linear quotients

Commutative Algebra 2024-12-24 v2 Combinatorics

Abstract

Let I(G)I(G) be the edge ideal of a gapfree graph GG. An open conjecture of Nevo and Peeva states that I(G)qI(G)^q has linear resolution for q0q\gg 0. We present a promising approach to this challenging conjecture by investigating the stronger property of linear quotients. Specifically, we make the conjecture that if I(G)qI(G)^q has linear quotients for some integer q1q\geq 1, then I(G)sI(G)^{s} has linear quotients for all sqs\geq q. We give a partial solution to this conjecture, and identify conditions under which only finitely many powers need to be checked. It is known that if GG does not contain a cricket, a diamond, or a C4C_4, then I(G)qI(G)^q has linear resolution for q2q \geq 2. We construct a family of gapfree graphs GG containing cricket, diamond, C4C_4 together with C5C_5 as induced subgraphs of GG for which I(G)qI(G)^q has linear quotients for q2q \ge 2.

Keywords

Cite

@article{arxiv.2412.06467,
  title  = {Gapfree graphs and powers of edge ideals with linear quotients},
  author = {Nursel Erey and Sara Faridi and Tài Huy Hà and Takayuki Hibi and Selvi Kara and Susan Morey},
  journal= {arXiv preprint arXiv:2412.06467},
  year   = {2024}
}

Comments

27 pages, 6 figures