A graph G with maximum degree and edge chromatic number (G)> is edge--critical if (G -e) = for every edge e of G. It is proved here that the vertex independence number of an edge--critical graph of order n is less than 3 5 n. For large , this improves on the best bound previously known, which was ro
Generalizations of independence and chromatic numbers of a graph
โ Scribed by E. Sampathkumar
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 426 KB
- Volume
- 115
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
Sampathkumar, E., Generalizations of independence and chromatic numbers of a graph, Discrete Mathematics 115 (1993) 2455251. Let G = (V, E) be a graph and k > 2 be an integer. A set S c V is k-independent if every component in the subgraph (S) induced by S has order at most k-1. The general chromatic number xP(G) of G is the minimum order n of a partition P of the set V such that each set V, in P is k-independent, This paper develops properties of x~(C) which are generalizations of well-known properties of chromatic number.
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