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Towards a Weighted Version of the Hajnal–Szemerédi Theorem

Published online by Cambridge University Press:  28 February 2013

JOZSEF BALOGH
Affiliation:
Department of Mathematical Sciences, University of Illinois, Urbana, IL 61801, USA (e-mail: [email protected])
GRAEME KEMKES
Affiliation:
Department of Mathematics, Ryerson University, Toronto, ON, M5B 2K3, Canada (e-mail: [email protected])
CHOONGBUM LEE
Affiliation:
Department of Mathematics, University of California, Los Angeles, Los Angeles, CA 90095, USA (e-mail: [email protected])
STEPHEN J. YOUNG
Affiliation:
Department of Mathematics, University of Louisville, Louisville, KY, 40292, UCS (e-mail: [email protected])

Abstract

For a positive integer r ≥ 2, a Kr-factor of a graph is a collection vertex-disjoint copies of Kr which covers all the vertices of the given graph. The celebrated theorem of Hajnal and Szemerédi asserts that every graph on n vertices with minimum degree at least $(1-\frac{1}{r})n contains a Kr-factor. In this note, we propose investigating the relation between minimum degree and existence of perfect Kr-packing for edge-weighted graphs. The main question we study is the following. Suppose that a positive integer r ≥ 2 and a real t ∈ [0, 1] is given. What is the minimum weighted degree of Kn that guarantees the existence of a Kr-factor such that every factor has total edge weight at least $$t\binom{r}{2}$?$ We provide some lower and upper bounds and make a conjecture on the asymptotics of the threshold as n goes to infinity.

Type
Paper
Copyright
Copyright © Cambridge University Press 2013

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References

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