Results 21 to 30 of about 382 (214)
Matchings Extend to Hamiltonian Cycles in 5-Cube
Ruskey and Savage asked the following question: Does every matching in a hypercube Qn for n ≥ 2 extend to a Hamiltonian cycle of Qn? Fink confirmed that every perfect matching can be extended to a Hamiltonian cycle of Qn, thus solved Kreweras’ conjecture.
Wang Fan, Zhao Weisheng
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The H-force sets of the graphs satisfying the condition of Ore’s theorem
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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Graphs with few hamiltonian cycles
We describe an algorithm for the exhaustive generation of non-isomorphic graphs with a given number k ≥
Goedgebeur, Jan +2 more
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The parity Hamiltonian cycle problem
Motivated by a relaxed notion of the celebrated Hamiltonian cycle, this paper investigates its variant, parity Hamiltonian cycle (PHC): A PHC of a graph is a closed walk which visits every vertex an odd number of times, where we remark that the walk may use an edge more than once. First, we give a complete characterization of the graphs which have PHCs,
Hiroshi Nishiyama +4 more
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Alternating Hamiltonian cycles in $2$-edge-colored multigraphs [PDF]
A path (cycle) in a $2$-edge-colored multigraph is alternating if no two consecutive edges have the same color. The problem of determining the existence of alternating Hamiltonian paths and cycles in $2$-edge-colored multigraphs is an $\mathcal{NP ...
Alejandro Contreras-Balbuena +2 more
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Removable matchings and hamiltonian cycles
The authors show the following two results: {\parindent=5mm \begin{itemize}\item[1)]Let \(G\) be a graph of order \(n\geq 4k+3\) with \(\sigma_2 (G)\geq n\) and let \(F\) be a matching of size \(k\) in \(G\) such that \(G-F\) is 2-connected. Then \(G-F\) is hamiltonian or \(G\cong K_2 +(K_2\cup K_{n-4})\) or \(G\cong \bar{K_2} +(K_2\cup K_{n-4 ...
Zhiquan Hu, Hao Li
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The Parity of Directed Hamiltonian Cycles [PDF]
We present a deterministic algorithm that given any directed graph on n vertices computes the parity of its number of Hamiltonian cycles in O(1.619^n) time and polynomial space. For bipartite graphs, we give a 1.5^n poly(n) expected time algorithm. Our algorithms are based on a new combinatorial formula for the number of Hamiltonian cycles modulo a ...
Björklund, Andreas, Husfeldt, Thore
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Hamiltonian Chains in Hypergraphs [PDF]
Hamiltionian chain is a generalisation of hamiltonian cycles for hypergraphs. Among the several possible ways of generalisations this is probably the most strong one, it requires the strongest structure.
Gyula Y. Katona
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Problems on Shortest k-Node Cycles and Paths
The paper is devoted to the construction of mathematical models for problems on the shortest cycles and paths, that pass through a given number of nodes of a directed graph.
Petro Stetsyuk +2 more
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Hamiltonian cycles in torical lattices [PDF]
We establish sufficient conditions for a toric lattice $T_{m,n}$ to be Hamiltonian. Also, we give some asymptotics for the number of Hamiltonian cycles in $T_{m,n}$.
Vladimir K. Leontiev
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