English

Unavoidable pivot-minors in graphs of large rank-depth

Combinatorics 2025-07-18 v1

Abstract

Shrub-depth and rank-depth are related graph parameters that are dense analogs of tree-depth. We prove that for every positive integer tt, every graph of sufficiently large rank-depth contains a pivot-minor isomorphic to a path on tt vertices or a graph consisting of two disjoint cliques of size tt joined by a half graph. This answers an open problem raised by Kwon, McCarty, Oum, and Wollan in 2021.

Keywords

Cite

@article{arxiv.2507.12697,
  title  = {Unavoidable pivot-minors in graphs of large rank-depth},
  author = {Jungho Ahn and Kevin Hendrey and O-joung Kwon and Sang-il Oum},
  journal= {arXiv preprint arXiv:2507.12697},
  year   = {2025}
}

Comments

15 pages, 5 figures