English

Perfect packings with complete graphs minus an edge

Combinatorics 2007-05-23 v1

Abstract

Let K_r^- denote the graph obtained from K_r by deleting one edge. We show that for every integer r\ge 4 there exists an integer n_0=n_0(r) such that every graph G whose order n\ge n_0 is divisible by r and whose minimum degree is at least (1-1/chi_{cr}(K_r^-))n contains a perfect K_r^- packing, i.e. a collection of disjoint copies of K_r^- which covers all vertices of G. Here chi_{cr}(K_r^-)=r(r-2)/(r-1) is the critical chromatic number of K_r^-. The bound on the minimum degree is best possible and confirms a conjecture of Kawarabayashi for large n.

Keywords

Cite

@article{arxiv.math/0605189,
  title  = {Perfect packings with complete graphs minus an edge},
  author = {Oliver Cooley and Daniela Kühn and Deryk Osthus},
  journal= {arXiv preprint arXiv:math/0605189},
  year   = {2007}
}