In this paper it is shown that any rn-regular graph of order 2rn (rn 3 3), not isomorphic to K, , , , or of order 2rn + 1 (rn even, rn 3 4), is Hamiltonian connected, which extends a previous result of Nash-Williams. As a corollary, it is derived that any such graph contains at least rn Hamiltonian
On hamiltonian-connected graphs
β Scribed by Ronald J. Gould; Xingxing Yu
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 735 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
One of the most fundamental results concerning paths in graphs is due to Ore: In a graph G, if deg x + deg y β§ |V(G)| + 1 for all pairs of nonadjacent vertices x, y β V(G), then G is hamiltonianβconnected. We generalize this result using set degrees. That is, for S β V(G), let deg S = |~xβ S~ N(x)|, where N(x) = {v|xv β E(G)} is the neighborhood of x. In particular we show: In a 3βconnected graph G, if deg S~1~ + deg S~2~ β§ |V(G)| + 1 for each pair of distinct 2βsets of vertices S~1~, S~2~ β V(G), then G is hamiltonianβconnected.
Several corollaries and related results are also discussed.
π SIMILAR VOLUMES
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