Results 11 to 20 of about 807 (75)
Decomposing tournaments into paths
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
wiley +1 more source
On Hamiltonian Cycles in Claw-Free Cubic Graphs
We show that every claw-free cubic graph of order n at least 8 has at most 2⌊n4⌋{2^{\left\lfloor {{n \over 4}} \right\rfloor }} Hamiltonian cycles, and we also characterize all extremal graphs.
Mohr Elena, Rautenbach Dieter
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The Existence of Path-Factor Covered Graphs
A spanning subgraph H of a graph G is called a P≥k-factor of G if every component of H is isomorphic to a path of order at least k, where k ≥ 2. A graph G is called a P≥k-factor covered graph if there is a P≥k-factor of G covering e for any e ∈ E(G).
Dai Guowei
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Equimatchable Bipartite Graphs
A graph is called equimatchable if all of its maximal matchings have the same size. Lesk et al. [Equi-matchable graphs, Graph Theory and Combinatorics (Academic Press, London, 1984) 239–254] has provided a characterization of equimatchable bipartite ...
Büyükçolak Yasemin+2 more
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Some Results on Path-Factor Critical Avoidable Graphs
A path factor is a spanning subgraph F of G such that every component of F is a path with at least two vertices. We write P≥k = {Pi : i ≥ k}. Then a P≥k-factor of G means a path factor in which every component admits at least k vertices, where k ≥ 2 is ...
Zhou Sizhong
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Strong Geodetic Problem in Networks
In order to model certain social network problems, the strong geodetic problem and its related invariant, the strong geodetic number, are introduced.
Manuel Paul+4 more
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If S = (a1, a2, . . .) is a non-decreasing sequence of positive integers, then an S-packing coloring of a graph G is a partition of V (G) into sets X1, X2, . . .
Brešar Boštjan+3 more
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Strong edge geodetic problem in networks
Geodesic covering problems form a widely researched topic in graph theory. One such problem is geodetic problem introduced by Harary et al. [Math. Comput. Modelling, 1993, 17, 89-95].
Manuel Paul+4 more
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The matching polynomial of a distance‐regular graph
A distance‐regular graph of diameter d has 2d intersection numbers that determine many properties of graph (e.g., its spectrum). We show that the first six coefficients of the matching polynomial of a distance‐regular graph can also be determined from its intersection array, and that this is the maximum number of coefficients so determined.
Robert A. Beezer, E. J. Farrell
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Further new results on strong resolving partitions for graphs
A set W of vertices of a connected graph G strongly resolves two different vertices x, y ∉ W if either d G(x, W) = d G(x, y) + d G(y, W) or d G(y, W) = d G(y, x) + d
Kuziak Dorota, Yero Ismael G.
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