Results 1 to 10 of about 80 (79)
Sparse Kneser graphs are Hamiltonian
Journal of the London Mathematical Society, Volume 103, Issue 4, Page 1253-1275, June 2021., 2021 Abstract For integers k⩾1 and n⩾2k+1, the Kneser graph K(n,k) is the graph whose vertices are the k‐element subsets of {1,…,n} and whose edges connect pairs of subsets that are disjoint. The Kneser graphs of the form K(2k+1,k) are also known as the odd graphs.
Torsten Mütze +2 more
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Toughness, Forbidden Subgraphs, and Hamilton-Connected Graphs
Discussiones Mathematicae Graph Theory, 2022 A graph G is called Hamilton-connected if for every pair of distinct vertices {u, v} of G there exists a Hamilton path in G that connects u and v. A graph G is said to be t-tough if t·ω(G − X) ≤ |X| for all X ⊆ V (G) with ω(G − X) > 1. The toughness of G,
Zheng Wei, Broersma Hajo, Wang Ligong
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On Implicit Heavy Subgraphs and Hamiltonicity of 2-Connected Graphs
Discussiones Mathematicae Graph Theory, 2021 A graph G of order n is implicit claw-heavy if in every induced copy of K1,3 in G there are two non-adjacent vertices with sum of their implicit degrees at least n. We study various implicit degree conditions (including, but not limiting to, Ore- and Fan-
Zheng Wei, Wideł Wojciech, Wang Ligong
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On Order Prime Divisor Graphs of Finite Groups
Discussiones Mathematicae - General Algebra and Applications, 2021 The order prime divisor graph 𝒫𝒟(G) of a finite group G is a simple graph whose vertex set is G and two vertices a, b ∈ G are adjacent if and only if either ab = e or o(ab) is some prime number, where e is the identity element of the group G and o(x ...
Sen Mridul K. +2 more
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Decomposing tournaments into paths
Proceedings of the London Mathematical Society, Volume 121, Issue 2, Page 426-461, August 2020., 2020 Abstract We consider a generalisation of Kelly's conjecture which is due to Alspach, Mason, and Pullman from 1976. Kelly's conjecture states that every regular tournament has an edge decomposition into Hamilton cycles, and this was proved by Kühn and Osthus for large tournaments. The conjecture of Alspach, Mason, and Pullman asks for the minimum number
Allan Lo +3 more
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Asymptotically sharpening the $s$-Hamiltonian index bound [PDF]
Discrete Mathematics & Theoretical Computer Science, 2022 For a non-negative integer $s\le |V(G)|-3$, a graph $G$ is $s$-Hamiltonian if the removal of any $k\le s$ vertices results in a Hamiltonian graph. Given a connected simple graph $G$ that is not isomorphic to a path, a cycle, or a $K_{1,3}$, let $\delta(G)
Sulin Song +3 more
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The H-force sets of the graphs satisfying the condition of Ore’s theorem
Open Mathematics, 2020 Let G be a Hamiltonian graph. A nonempty vertex set X⊆V(G)X\subseteq V(G) is called a Hamiltonian cycle enforcing set (in short, an H-force set) of G if every X-cycle of G (i.e., a cycle of G containing all vertices of X) is a Hamiltonian cycle.
Zhang Xinhong, Li Ruijuan
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Forbidden Subgraphs for Existences of (Connected) 2-Factors of a Graph
Discussiones Mathematicae Graph Theory, 2023 Clearly, having a 2-factor in a graph is a necessary condition for a graph to be hamiltonian, while having an even factor in graph is a necessary condition for a graph to have a 2-factor.
Yang Xiaojing, Xiong Liming
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Forbidden Subgraphs for Collapsible Graphs and Supereulerian Graphs
Discussiones Mathematicae Graph Theory, 2022 In this paper, we completely characterize the connected forbidden subgraphs and pairs of connected forbidden subgraphs that force a 2-edge-connected (2-connected) graph to be collapsible.
Liu Xia, Xiong Liming
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Hamilton cycles in almost distance-hereditary graphs
Open Mathematics, 2016 Let G be a graph on n ≥ 3 vertices. A graph G is almost distance-hereditary if each connected induced subgraph H of G has the property dH(x, y) ≤ dG(x, y) + 1 for any pair of vertices x, y ∈ V(H).
Chen Bing, Ning Bo
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