English

Triangles in $K_s$-saturated graphs with minimum degree $t$

Combinatorics 2019-06-06 v1

Abstract

For n15n \geq 15, we prove that the minimum number of triangles in an nn-vertex K4K_4-saturated graph with minimum degree 4 is exactly 2n42n-4, and that there is a unique extremal graph. This is a triangle version of a result of Alon, Erd\H{o}s, Holzman, and Krivelevich from 1996. Additionally, we show that for any s>r3s > r \geq 3 and t2(s2)+1t \geq 2 (s-2)+1, there is a KsK_s-saturated nn-vertex graph with minimum degree tt that has (s2r1)2r1n+cs,r,t\binom{ s-2}{r-1}2^{r-1} n + c_{s,r,t} copies of KrK_r. This shows that unlike the number of edges, the number of KrK_r's (r>2r >2) in a KsK_s-saturated graph is not forced to grow with the minimum degree, except for possibly in lower order terms.

Keywords

Cite

@article{arxiv.1906.02154,
  title  = {Triangles in $K_s$-saturated graphs with minimum degree $t$},
  author = {Benjamin Cole and Albert Curry and David Davini and Craig Timmons},
  journal= {arXiv preprint arXiv:1906.02154},
  year   = {2019}
}

Comments

22 pages

R2 v1 2026-06-23T09:43:46.756Z