English

Induced subdivisions with pinned branch vertices

Combinatorics 2025-04-08 v3

Abstract

We prove that for all rN{0}r\in \mathbb{N}\cup \{0\} and s,tNs,t\in \mathbb{N}, there exists Ω=Ω(r,s,t)N\Omega=\Omega(r,s,t)\in \mathbb{N} with the following property. Let GG be a graph and let HH be a subgraph of GG isomorphic to a (r)(\leq r)-subdivision of KΩK_{\Omega}. Then either GG contains KtK_t or Kt,tK_{t,t} as an induced subgraph, or there is an induced subgraph JJ of GG isomorphic to a proper (r)(\leq r)-subdivision of KsK_s such that every branch vertex of JJ is a branch vertex of HH. This answers in the affirmative a question of Lozin and Razgon. In fact, we show that both the branch vertices and the paths corresponding to the subdivided edges between them can be preserved.

Keywords

Cite

@article{arxiv.2308.01502,
  title  = {Induced subdivisions with pinned branch vertices},
  author = {Sepehr Hajebi},
  journal= {arXiv preprint arXiv:2308.01502},
  year   = {2025}
}
R2 v1 2026-06-28T11:46:57.986Z