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A generalization of Ore's Theorem involving neighborhood unions

✍ Scribed by H.J. Broersma; J. van den Heuvel; H.J. Veldman


Publisher
Elsevier Science
Year
1993
Tongue
English
Weight
656 KB
Volume
122
Category
Article
ISSN
0012-365X

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✦ Synopsis


Let G be a graph of order n. Settling conjectures of Chen and Jackson, we prove the following generalization of Ore's Theorem: If G is 2-connected and )N(u)u N(v)1 >:n for every pair of nonadjacent vertices a, u, then either G is hamiltonian, or G is the Petersen graph, or G belongs to one of three families of exceptional graphs of connectivity 2.


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