ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

IMPACT FACTOR 2018: 0.741

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Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory 24(3) (2004) 545-549
DOI: 10.7151/dmgt.1252


Lucien Haddad and Claude Tardif

Department of Mathematics and Computer Science
Royal Military College of Canada
PO Box 17000, Station "Forces"
Kingston, Ontario K7K 7B4 Canada


The Erdős-Faber-Lovász conjecture states that if a graph G is the union of n cliques of size n no two of which share more than one vertex, then χ(G) = n. We provide a formulation of this conjecture in terms of maximal partial clones of partial operations on a set.

Keywords: chromatic number, Erdős-Faber-Lovász conjecture, maximal partial clones.

2000 Mathematics Subject Classification: 05C15 (primary: graph colouring) 08A55 (secondary: Partial algebras).


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Received 12 July 2004