Graph colourings and partitions
نویسندگان
چکیده
منابع مشابه
Graph colourings and partitions
In this paper we have investigated mainly the three colouring parameters of a graph G, viz., the chromatic number, the achromatic number and the pseudoachromatic number. The importance of their study in connection with the computational complexity, partitions, algebra, projective plane geometry and analysis were brie.y surveyed. Some new results were found along these directions. We have rede0n...
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Erdős and Lovász conjectured in 1968 that for every graph G with χ(G) > ω(G) and any two integers s, t ≥ 2 with s+ t = χ(G)+1, there is a partition (S, T ) of the vertex set V (G) such that χ(G[S]) ≥ s and χ(G[T ]) ≥ t. Except for a few cases, this conjecture is still unsolved. In this note we prove the conjecture for line graphs of multigraphs.
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2001
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(00)00231-0