A neighborhood and degree condition for pancyclicity and vertex pancyclicity

Ryota Matsubara, Masao Tsugaki, Tomoki Yamashita

Research output: Contribution to journalArticle

Abstract

Let G be a 2-connected graph of order n. For any u ∈ V (G) and l ∈ {m, m + 1,..., n}, if G has a cycle of length l, then G is called [m, n]-pancyclic, and if G has a cycle of length l which contains u, then G is called [m, n]-vertex pancyclic. Let δ(G) be a minimum degree of G and let NG(x) be the neighborhood of a vertex x in G. In [Australas. J. Combin. 12 (1995), 81-91] Liu, Lou and Zhao proved that if |NG(u) ∪ NG(v)| + δ(G) ≥ n + 1 for any nonadjacent vertices u, v of G, then G is [3, n]-vertex pancyclic. In this paper, we prove if n ≥ 6 and |NG(u)∪NG(v)|+dG(w) ≥ n for every triple independent vertices u, v, w of G, then (i) G is [3,n]-pancyclic or isomorphic to the complete bipartite graph Kn/2,n/2, and (ii) G is [5, n]-vertex pancyclic or isomorphic to the complete bipartite graph Kn/2,n/2.

Original languageEnglish
Pages (from-to)15-25
Number of pages11
JournalAustralasian Journal of Combinatorics
Volume40
Publication statusPublished - 2008
Externally publishedYes

ASJC Scopus subject areas

  • Discrete Mathematics and Combinatorics

Cite this

A neighborhood and degree condition for pancyclicity and vertex pancyclicity. / Matsubara, Ryota; Tsugaki, Masao; Yamashita, Tomoki.

In: Australasian Journal of Combinatorics, Vol. 40, 2008, p. 15-25.

Research output: Contribution to journalArticle

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