Results 51 to 60 of about 238 (93)
Discussiones Mathematicae Graph Theory, 2018 A total-colored graph G is rainbow total-connected if any two vertices of G are connected by a path whose edges and internal vertices have distinct colors.
Sun Yuefang, Jin Zemin, Tu Jianhua
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Singular Turán Numbers and Worm-Colorings
Discussiones Mathematicae Graph Theory, 2022 A subgraph G of H is singular if the vertices of G either have the same degree in H or have pairwise distinct degrees in H. The largest number of edges of a graph on n vertices that does not contain a singular copy of G is denoted by TS(n, G).
Gerbner Dániel +3 more
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Some results on the total proper k-connection number
Open Mathematics, 2022 In this paper, we first investigate the total proper connection number of a graph GG according to some constraints of G¯\overline{G}. Next, we investigate the total proper connection numbers of graph GG with large clique number ω(G)=n−s\omega \left(G)=n ...
Ma Yingbin, Zhang Hui
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Bounds on F-index of tricyclic graphs with fixed pendant vertices
Open Mathematics, 2020 The F-index F(G) of a graph G is obtained by the sum of cubes of the degrees of all the vertices in G. It is defined in the same paper of 1972 where the first and second Zagreb indices are introduced to study the structure-dependency of total π-electron ...
Akram Sana +2 more
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Maximum Edge-Colorings Of Graphs
Discussiones Mathematicae Graph Theory, 2016 An r-maximum k-edge-coloring of G is a k-edge-coloring of G having a property that for every vertex v of degree dG(v) = d, d ≥ r, the maximum color, that is present at vertex v, occurs at v exactly r times. The r-maximum index χr′(G)$\chi _r^\prime (G)$
Jendrol’ Stanislav +1 more
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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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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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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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