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arXiv · 0907.3815

Dense H-free graphs are almost (χ(H)-1)-partite

Peter Allen
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Abstract

By using the Szemerédi Regularity Lemma, Alon and Sudakov recently extended the classical Andrásfai-Erdõs-Sós theorem to cover general graphs. We prove, without using the Regularity Lemma, that the following stronger statement is true. Given any (r-1)-partite graph H whose smallest part has t vertices, and any fixed c>0, there exists a constant C such that whenever G is an n-vertex graph with minimum degree at least ((3r-4)/(3r-1)+c)n, either G contains H, or we can delete at most Cn^(2-1/t) edges from G to yield an r-partite graph.

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Peter Allen. 2011-02-16. Dense H-free graphs are almost (χ(H)-1)-partite. https://arxiv.org/abs/0907.3815

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