ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

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Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory 24(2) (2004) 183-195
DOI: 10.7151/dmgt.1224


Massimiliano Caramia

IAC - Istituto per le Applicazioni del Calcolo "M. Picone"
CNR - Viale del Policlinico, 137 - 00161 Roma, Italy


Jirí Fiala

Institute of Theoretical Computer Science (ITI)
Charles University, Faculty of Mathematics and Physics
Malostranské nám. 2/25, 118 00, Prague, Czech Republic



In this paper we present theoretical and algorithmic results for the computation of lower bounds on the chromatic number of a weighted graph. In particular, we study different ways of a possible improvement of the lower bound offered by a maximum weighted clique. Based on our findings we devise new algorithms and show their performance on random graphs.

Keywords: combinatorial analysis, computational analysis, optimization.

2000 Mathematics Subject Classification: 05C15, 05C85.


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Received 13 May 2002
Revised 27 October 2003