Let i be a positive integer. We generalize the chromatic number x ( G ) of G and the clique number w(G) of G as follows: The i-chromatic number of G , denoted by x Z ( G ) , is the least number k for which G has a vertex partition V,, V,, . . . , Vk: such that the clique number of the subgraph induc
A common generalization of line graphs and clique graphs
β Scribed by Erich Prisner
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 664 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Both the line graph and the clique graph are defined as intersection graphs of certain families of complete subgraphs of a graph. We generalize this concept. By a kβedge of a graph we mean a complete subgraph with k vertices or a clique with fewer than k vertices. The kβedge graph Ξ__~k~(G__) of a graph G is defined as the intersection graph of the set of all kβedges of G. The following three problems are investigated for kβedge graphs. The first is the characterization problem. Second, sets of graphs closed under the kβedge graph operator are found. The third problem is the question of convergence: What happens to a graph if we take iterated kβedge graphs?
π SIMILAR VOLUMES
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