English

The extremal functions for triangle-free graphs with excluded minors

Combinatorics 2018-07-18 v2

Abstract

We prove two results: 1. A graph GG on at least seven vertices with a vertex vv such that GvG-v is planar and tt triangles satisfies E(G)3V(G)9+t/3|E(G)| \leq 3|V(G)|- 9 + t/3. 2. For p=2,3,,9p=2,3,\ldots,9, a triangle-free graph GG on at least 2p52p-5 vertices with no KpK_p-minor satisfies E(G)(p2)V(G)(p2)2|E(G)|\leq (p-2)|V(G)| - (p-2)^2.

Keywords

Cite

@article{arxiv.1801.06887,
  title  = {The extremal functions for triangle-free graphs with excluded minors},
  author = {Robin Thomas and Youngho Yoo},
  journal= {arXiv preprint arXiv:1801.06887},
  year   = {2018}
}

Comments

12 pages, no figures. Revised according to referees' comments

R2 v1 2026-06-22T23:51:22.447Z