Hamiltonicity of regular 2-connected graphs
β Scribed by Broersma, H. J.; van den Heuvel, J.; Jackson, B.; Veldman, H. J.
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 832 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Let G be a k-regular 2-connected graph of order n. Jackson proved that G is hamiltonian if n 5 3k. Zhu and Li showed that the upper bound 3k on n can be relaxed to q k if G is 3-connected and k 2 63. We improve both results by showing that G is hamiltonian if n 5 gk -7 and G does not belong to a restricted class 3 of nonhamiltonian graphs of connectivity 2. To establish this result we obtain a variation of Woodall's Hopping Lemma and use it to prove that if n 5 $ k -7 and G has a dominating cycle (i.e., a cycle such that the vertices off the cycle constitute an independent set), then G is hamiltonian. We also prove that if n 5 4k -3 and G $ 3, then G has a dominating cycle. For k 2 4 it is conjectured that G is hamiltonian if n 5 4k and G $ 3.
π SIMILAR VOLUMES
Let G be a 2-connected d-regular graph on n rd (r 3) vertices and c(G) denote the circumference of G. Bondy conjectured that c(G) 2nΓ(r&1) if n is large enough. In this paper, we show that c(G) 2nΓ(r&1)+2(r&3)Γ(r&1) for any integer r 3. In particular, G is hamiltonian if r=3. This generalizes a resu
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
## Abstract Let __T__ be the line graph of the unique tree __F__ on 8 vertices with degree sequence (3,3,3,1,1,1,1,1), i.e., __T__ is a chain of three triangles. We show that every 4βconnected {__T__, __K__~1,3~}βfree graph has a hamiltonian cycle. Β© 2005 Wiley Periodicals, Inc. J Graph Theory 49:
## UNIVERSIW OF WATERLOO ' The research reported here has been sponsored by the Canadian Commonwealth Association.
## Abstract The topological approach to the study of infinite graphs of Diestel and KΓhn has enabled several results on Hamilton cycles in finite graphs to be extended to locally finite graphs. We consider the result that the line graph of a finite 4βedgeβconnected graph is hamiltonian. We prove a