For an integer i, a graph is called an L,-graph if, for each triple of vertices u, u , w with and Khachatrian proved that connected Lo-graphs of order a t least 3 are hamiltonian, thus improving Ore's Theorem. All K1,3-free graphs are L1-graphs, whence recognizing hamiltonian L1-graphs is an NP-com
A characterization of panconnected graphs satisfying a local ore-type condition
✍ Scribed by Asratian, A. S.; H�ggkvist, R.; Sarkisian, G. V.
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 491 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0364-9024
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✦ Synopsis
It is well known that a graph G of orderp 2 3 is Hamilton-connected if d(u) +d(v) 2 p + 1 for each pair of nonadjacent vertices u and w. In this paper we consider connected graphs G of order at least 3 for which
where N ( z ) denote the neighborhood of a vertex z. We prove that a graph G satisfying this condition has the following properties: (a) For each pair of nonadjacent vertices z, y of G and for each integer k , d(z, y) I k I IV(G)l -1, there is an zy path of length k . (b) For each edge xy of G and for each integer k (excepting maybe one k E {3,4}) there is a cycle of length k containing zy.
Consequently G is panconnected (and also edge pancyclic) if and only if each edge of
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