Let f (v, e, Ξ») denote the maximum number of proper vertex colorings of a graph with v vertices and e edges in Ξ» colors. In this paper we present some new upper bounds for f (v, e, Ξ»). In particular, a new notion of pseudoproper colorings of a graph is given, which allows us to significantly improve
New upper bounds for the greatest number of proper colorings of a (V,E)-graph
β Scribed by Felix Lazebnik
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 185 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Abstract
Let π» denote the family of simple undirected graphs on v vertices having e edges ((v, e)βgraphs) and P(G; Ξ») be the chromatic polynomial of a graph G. For the given integers v, e, and Ξ», let f(v, e, Ξ») denote the greatest number of proper colorings in Ξ» or less colors that a (v, e)βgraph G can have, i.e., f(v, e, Ξ») = max{P(G; Ξ»): G β π»}. In this paper we determine some new upper bounds for f(v, e, Ξ»).
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