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Covering Two-Edge-Coloured Complete Graphs with Two Disjoint Monochromatic Cycles

Published online by Cambridge University Press:  01 July 2008

PETER ALLEN*
Affiliation:
Department of Mathematics, London School of Economics, Houghton Street, London WC2A 2AE, UK (e-mail: [email protected])

Abstract

In 1998 Łuczak Rödl and Szemerédi [7] proved, by means of the Regularity Lemma, that there exists n0 such that, for any nn0 and two-edge-colouring of Kn, there exists a pair of vertex-disjoint monochromatic cycles of opposite colours covering the vertices of Kn. In this paper we make use of an alternative method of finding useful structure in a graph, leading to a proof of the same result with a much smaller value of n0. The proof gives a polynomial-time algorithm for finding the two cycles.

Type
Paper
Copyright
Copyright © Cambridge University Press 2008

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