Results 71 to 80 of about 1,202 (110)
Half domination arrangements in regular and semi-regular tessellation type graphs [PDF]
, 2012 We study the problem of half-domination sets of vertices in vertex transitive infinite graphs generated by regular or semi-regular tessellations of the plane.
Ionascu, Eugen J.
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The Minimum Harmonic Index for Unicyclic Graphs with Given Diameter
Discussiones Mathematicae Graph Theory, 2018 The harmonic index of a graph G is defined as the sum of the weights 2d(u)+d(v)${2 \over {d(u) + d(v)}}$ of all edges uv of G, where d(u) denotes the degree of a vertex u in G.
Zhong Lingping
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Spectral Radius and Hamiltonicity of Graphs
Discussiones Mathematicae Graph Theory, 2019 In this paper, we study the Hamiltonicity of graphs with large minimum degree. Firstly, we present some conditions for a simple graph to be Hamilton-connected and traceable from every vertex in terms of the spectral radius of the graph or its complement,
Yu Guidong +3 more
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A Note on Upper Bounds for Some Generalized Folkman Numbers
Discussiones Mathematicae Graph Theory, 2019 We present some new constructive upper bounds based on product graphs for generalized vertex Folkman numbers. They lead to new upper bounds for some special cases of generalized edge Folkman numbers, including the cases Fe(K3, K4 − e; K5) ≤ 27 and Fe(K4 −
Xu Xiaodong +2 more
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An extremal problem on potentially $K_{m}-P_{k}$-graphic sequences
, 2005 A sequence $S$ is potentially $K_{m}-P_{k}$ graphical if it has a realization containing a $K_{m}-P_{k}$ as a subgraph. Let $\sigma(K_{m}-P_{k}, n)$ denote the smallest degree sum such that every $n$-term graphical sequence $S$ with $\sigma(S)\geq \sigma(
Lai, Chunhui
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Saturation Spectrum of Paths and Stars
Discussiones Mathematicae Graph Theory, 2017 A graph G is H-saturated if H is not a subgraph of G but the addition of any edge from G̅ to G results in a copy of H. The minimum size of an H-saturated graph on n vertices is denoted sat(n,H), while the maximum size is the well studied extremal number,
Faudree Jill +4 more
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Another View of Bipartite Ramsey Numbers
Discussiones Mathematicae Graph Theory, 2018 For bipartite graphs F and H and a positive integer s, the s-bipartite Ramsey number BRs(F,H) of F and H is the smallest integer t with t ≥ s such that every red-blue coloring of Ks,t results in a red F or a blue H.
Bi Zhenming, Chartrand Gary, Zhang Ping
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An efficient asymmetric removal lemma and its limitations
Forum of Mathematics, SigmaThe triangle removal states that if G contains $\varepsilon n^2$ edge-disjoint triangles, then G contains $\delta (\varepsilon )n^3$ triangles. Unfortunately, there are no sensible bounds on the order of growth of $\delta (\varepsilon )$
Lior Gishboliner +2 more
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Turán Function and H-Decomposition Problem for Gem Graphs
Discussiones Mathematicae Graph Theory, 2018 Given a graph H, the Turán function ex(n,H) is the maximum number of edges in a graph on n vertices not containing H as a subgraph. For two graphs G and H, an H-decomposition of G is a partition of the edge set of G such that each part is either a single
Liu Henry, Sousa Teresa
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On Nordhaus-Gaddum type relations of δ-complement graphs. [PDF]
Heliyon, 2023 Vichitkunakorn P +2 more
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