A characterization of graphs G with G ≈ K2(G)
✍ Scribed by Chai-Ling Deng; Chong-Keang Lim
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 311 KB
- Volume
- 151
- Category
- Article
- ISSN
- 0012-365X
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✦ Synopsis
A graph G is called a D-graph if for every set of cliques of G whose pairwise intersections are nonempty there is a vertex of G common to all the cliques of the set. A D-graph G is called a Dl-graph if it has the T 1 property: for any two distinct vertices x and y of G, there exist cliques C and D of G such that x ~ C but y¢ C and yeD but xcD.
Lim proved that if G is a Dl-graph, then G ~ K2(G). Motivated by this result of Lim, we ask the following question:
Can one characterize those graphs G with G ~ KS(G)?
In this paper, we prove that in the class of D-graphs, G ~ KS(G) if and only if G has the T1 property.
📜 SIMILAR VOLUMES
Let G be a graph with vertex set V and let g, f : V Ä Z + . We say that G has all ( g, f )-factors if G has an h-factor for every h: V Ä Z + such that g(v) h(v) f (v) for every v # V and at least one such h exists. In this note, we derive from Tutte's f-factor theorem a similar characterization for