Results 51 to 60 of about 167 (98)
On the Independence Number of Traceable 2-Connected Claw-Free Graphs
Discussiones Mathematicae Graph Theory, 2019 A well-known theorem by Chvátal-Erdőos [A note on Hamilton circuits, Discrete Math. 2 (1972) 111–135] states that if the independence number of a graph G is at most its connectivity plus one, then G is traceable.
Wang Shipeng, Xiong Liming
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The 2-pebbling property of squares of paths and Graham’s conjecture
Open Mathematics, 2020 A pebbling move on a graph G consists of taking two pebbles off one vertex and placing one pebble on an adjacent vertex. The pebbling number of a connected graph G, denoted by f(G), is the least n such that any distribution of n pebbles on G allows one ...
Li Yueqing, Ye Yongsheng
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Packing Coloring of Some Undirected and Oriented Coronae Graphs
Discussiones Mathematicae Graph Theory, 2017 The packing chromatic number χρ(G) of a graph G is the smallest integer k such that its set of vertices V(G) can be partitioned into k disjoint subsets V1, . . . , Vk, in such a way that every two distinct vertices in Vi are at distance greater than i in
Laïche Daouya +2 more
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Decomposition of Certain Complete Bipartite Graphs into Prisms
Discussiones Mathematicae Graph Theory, 2017 Häggkvist [6] proved that every 3-regular bipartite graph of order 2n with no component isomorphic to the Heawood graph decomposes the complete bipartite graph K6n,6n.
Froncek Dalibor
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Cores, Joins and the Fano-Flow Conjectures
Discussiones Mathematicae Graph Theory, 2018 The Fan-Raspaud Conjecture states that every bridgeless cubic graph has three 1-factors with empty intersection. A weaker one than this conjecture is that every bridgeless cubic graph has two 1-factors and one join with empty intersection.
Jin Ligang +2 more
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Core Index of Perfect Matching Polytope for a 2-Connected Cubic Graph
Discussiones Mathematicae Graph Theory, 2018 For a 2-connected cubic graph G, the perfect matching polytope P(G) of G contains a special point xc=(13,13,…,13)$x^c = \left( {{1 \over 3},{1 \over 3}, \ldots ,{1 \over 3}} \right)$ . The core index ϕ(P(G)) of the polytope P(G) is the minimum number of
Wang Xiumei, Lin Yixun
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A note on the edge general position number of cactus graphs
Open MathematicsFor a given graph G, a subset S of E(G) is an edge general position set of G if no triple of S is contained in a common shortest path. The cardinality of a largest edge general position set of G is called the edge general position number of G, denoted by
Cao Yahan, Ji Shengjin
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Degree-based topological properties of borophene sheets
Main Group Metal ChemistryThis study examines many innovative topological numbers and establishes mathematical interpretations for boron clusters and borophene coverings. The general Randic index, arithmetic index, and Albertson index are discussed in this work for the alpha ...
Al Khabyah Ali +3 more
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A sharp lower bound on the signless Laplacian index of graphs with (κ,τ)-regular sets
Special Matrices, 2018 A new lower bound on the largest eigenvalue of the signless Laplacian spectra for graphs with at least one (κ,τ)regular set is introduced and applied to the recognition of non-Hamiltonian graphs or graphs without a perfect matching.
Andeelić Milica +2 more
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C7-Decompositions of the Tensor Product of Complete Graphs
Discussiones Mathematicae Graph Theory, 2017 In this paper we consider a decomposition of Km × Kn, where × denotes the tensor product of graphs, into cycles of length seven. We prove that for m, n ≥ 3, cycles of length seven decompose the graph Km × Kn if and only if (1) either m or n is odd and (2)
Manikandan R.S., Paulraja P.
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