English

A stability theorem for multi-partite graphs

Combinatorics 2026-01-14 v1

Abstract

The Erd\H{o}s-Simonovits stability theorem is one of the most widely used theorems in extremal graph theory. We obtain an Erd\H{o}s-Simonovits type stability theorem in multi-partite graphs. Different from the Erd\H{o}s-Simonovits stability theorem, our stability theorem in multi-partite graphs says that if the number of edges of an HH-free graph GG is close to the extremal graphs for HH, then GG has a well-defined structure but may be far away to the extremal graphs for HH. As an application, we solve a conjecture posed by Han and Zhao concerning the maximum number of edges in multi-partite graphs which does not contain vertex-disjoint copies of a clique

Keywords

Cite

@article{arxiv.2208.13995,
  title  = {A stability theorem for multi-partite graphs},
  author = {Wanfang Chen and Changhong Lu and Long-Tu Yuan},
  journal= {arXiv preprint arXiv:2208.13995},
  year   = {2026}
}
R2 v1 2026-06-25T02:04:39.908Z