Results 11 to 20 of about 842 (102)
Strong Geodetic Problem in Networks
Discussiones Mathematicae Graph Theory, 2020 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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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
wiley +1 more source
Discussiones Mathematicae Graph Theory, 2020 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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Minimally Strong Subgraph (k,ℓ)-Arc-Connected Digraphs
Discussiones Mathematicae Graph Theory, 2022 Let D = (V,A) be a digraph of order n, S a subset of V of size k and 2 ≤ k ≤ n. A subdigraph H of D is called an S-strong subgraph if H is strong and S ⊆ V (H). Two S-strong subgraphs D1 and D2 are said to be arc-disjoint if A(D1) ∩ A(D2) = ∅.
Sun Yuefang, Jin Zemin
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Distance-based Indices Computation of Symmetry Molecular Structures
Open Journal of Mathematical Sciences, 2018 Most of molecular structures have symmetrical characteristics. It inspires us to calculate the topological indices by means of group theory. In this paper, we present the formulations for computing the several distance-based topological indices using ...
Li Yan, M. Farahani, Wei Gao
semanticscholar +1 more source
Path Decomposition Number of Certain Graphs
Open Journal of Discrete Applied Mathematics, 2018 Let G be a simple, finite and connected graph. A graph is said to be decomposed into subgraphs H1 and H2 which is denoted by G = H1 ⊕H2, if G is the edge disjoint union of H1 and H2.
O. Oyewumi, A. Akwu, Theresa Iveren Azer
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On Leighton's graph covering theorem [PDF]
, 2009 We give short expositions of both Leighton's proof and the Bass-Kulkarni proof of Leighton's graph covering theorem, in the context of colored graphs. We discuss a further generalization, needed elsewhere, to "symmetry-restricted graphs". We can prove it
W. Neumann
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Connected Edge Litact Domination in Graphs
International Journal of Innovative Technology and Exploring Engineering, 2019 A subset of edges dominating in is connected edge dominating, if , the subgraph induced by is connected.The connected edge litact domination number , is .In This article we could able to bring up some interesting results on connected edge litact ...
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On the Number of Disjoint 4-Cycles in Regular Tournaments
Discussiones Mathematicae Graph Theory, 2018 In this paper, we prove that for an integer r ≥ 1, every regular tournament T of degree 3r − 1 contains at least 2116r-103${{21} \over {16}}r - {{10} \over 3}$ disjoint directed 4-cycles. Our result is an improvement of Lichiardopol’s theorem when taking
Ma Fuhong, Yan Jin
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Graphs that are Critical for the Packing Chromatic Number
Discussiones Mathematicae Graph Theory, 2022 Given a graph G, a coloring c : V (G) → {1, …, k} such that c(u) = c(v) = i implies that vertices u and v are at distance greater than i, is called a packing coloring of G.
Brešar Boštjan, Ferme Jasmina
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