Displaying similar documents to “Long cycles in certain graphs of large degree.”

Vertex-dominating cycles in 2-connected bipartite graphs

Tomoki Yamashita (2007)

Discussiones Mathematicae Graph Theory

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A cycle C is a vertex-dominating cycle if every vertex is adjacent to some vertex of C. Bondy and Fan [4] showed that if G is a 2-connected graph with δ(G) ≥ 1/3(|V(G)| - 4), then G has a vertex-dominating cycle. In this paper, we prove that if G is a 2-connected bipartite graph with partite sets V₁ and V₂ such that δ(G) ≥ 1/3(max{|V₁|,|V₂|} + 1), then G has a vertex-dominating cycle.

Heavy Subgraph Conditions for Longest Cycles to Be Heavy in Graphs

Binlong Lia, Shenggui Zhang (2016)

Discussiones Mathematicae Graph Theory

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Let G be a graph on n vertices. A vertex of G with degree at least n/2 is called a heavy vertex, and a cycle of G which contains all the heavy vertices of G is called a heavy cycle. In this note, we characterize graphs which contain no heavy cycles. For a given graph H, we say that G is H-heavy if every induced subgraph of G isomorphic to H contains two nonadjacent vertices with degree sum at least n. We find all the connected graphs S such that a 2-connected graph G being S-heavy implies...

Large Degree Vertices in Longest Cycles of Graphs, I

Binlong Li, Liming Xiong, Jun Yin (2016)

Discussiones Mathematicae Graph Theory

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In this paper, we consider the least integer d such that every longest cycle of a k-connected graph of order n (and of independent number α) contains all vertices of degree at least d.

On long cycles through four prescribed vertices of a polyhedral graph

Jochen Harant, Stanislav Jendrol', Hansjoachim Walther (2008)

Discussiones Mathematicae Graph Theory

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For a 3-connected planar graph G with circumference c ≥ 44 it is proved that G has a cycle of length at least (1/36)c+(20/3) through any four vertices of G.

Forbidden Pairs and (k,m)-Pancyclicity

Charles Brian Crane (2017)

Discussiones Mathematicae Graph Theory

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A graph G on n vertices is said to be (k, m)-pancyclic if every set of k vertices in G is contained in a cycle of length r for each r ∈ {m, m+1, . . . , n}. This property, which generalizes the notion of a vertex pancyclic graph, was defined by Faudree, Gould, Jacobson, and Lesniak in 2004. The notion of (k, m)-pancyclicity provides one way to measure the prevalence of cycles in a graph. We consider pairs of subgraphs that, when forbidden, guarantee hamiltonicity for 2-connected graphs...

Characterization of semientire graphs with crossing number 2

D. G. Akka, J. K. Bano (2002)

Mathematica Bohemica

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The purpose of this paper is to give characterizations of graphs whose vertex-semientire graphs and edge-semientire graphs have crossing number 2. In addition, we establish necessary and sufficient conditions in terms of forbidden subgraphs for vertex-semientire graphs and edge-semientire graphs to have crossing number 2.