## 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
On the greatest number of 2 and 3 colorings of a (v, e)-graph
β Scribed by Felix Lazebnik
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- English
- Weight
- 446 KB
- Volume
- 13
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Let 9 denote the family of simple undirected graphs on u vertices having e edges ( ( u , el-graphs) and P(A, G ) be the chromatic polynomial of a graph G. For the given integers u, e, A, let f b , e, A) denote the greatest number of proper colorings in A or less colors that a (u, e)-graph G can have, i.e., f(u, e, A) =' max{P(A, G): G E 9}. In this paper we determine f(u, e, 2) and describe all graphs G for which P(2, G ) = f(u, e, 2). For f(u, e, 3). a lower bound and an upper bound are found. *This paper forms a part of a Ph.D. thesis written by the author under the supervision of Prof. H. S. Wilf at the University of Pennsylvania.
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