English

LF-Covers and Binomial Edge Ideals of K\"{o}nig Type

Commutative Algebra 2024-12-16 v4

Abstract

We give a combinatorial characterisation of connected graphs whose binomial edge ideals are of K\"{o}nig type, developed independently to the similar characterisation given by LaClair in arXiv:2304.13299, and exhibit some classes of graphs satisfying our criteria. For any connected Hamiltonian graph GG on nn vertices, we compute an explicit root of HJ(G)n1(R)H_{J(G)}^{n-1}(R) as an FF-finite FF-module.

Keywords

Cite

@article{arxiv.2310.14410,
  title  = {LF-Covers and Binomial Edge Ideals of K\"{o}nig Type},
  author = {David Williams},
  journal= {arXiv preprint arXiv:2310.14410},
  year   = {2024}
}

Comments

21 pages, v4 includes more examples of LF-covers and strengthens the uniquness result of the main theorem; v3 substantially reorganises v2, several proofs have been simplified or rewritten for clarity, and small errors have been corrected (whilst the numbering has changed, no new results are introduced)