Results 1 to 10 of about 163 (126)
On the number of edges of a simple Z 2 × Z 2-connected graph
Open MathematicsLuo, Xu and Yu proposed an extremal problem on group connectivity of graphs as follows: for an abelian group A with |A| ≥ 3 and an integer n ≥ 3, find ex(n, A), where ex(n, A) is the maximum number such that every simple graph with n vertices and at most
Zhang Yue, Yin Jian-Hua
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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 optimal pebbling of spindle graphs
Open Mathematics, 2019 Given a distribution of pebbles on the vertices of a connected graph G, a pebbling move on G consists of taking two pebbles off one vertex and placing one on an adjacent vertex. The optimal pebbling number of G, denoted by πopt(G), is the smallest number
Gao Ze-Tu, Yin Jian-Hua
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A Parametric Network Approach for Concepts Hierarchy Generation in Text Corpus
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2016 The article presents a preflow approach for the parametric maximum flow problem, derived from the rules of constructing concepts hierarchy in text corpus.
Sângeorzan L. S. +2 more
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Rainbow Vertex-Connection and Forbidden Subgraphs
Discussiones Mathematicae Graph Theory, 2018 A path in a vertex-colored graph is called vertex-rainbow if its internal vertices have pairwise distinct colors. A vertex-colored graph G is rainbow vertex-connected if for any two distinct vertices of G, there is a vertex-rainbow path connecting them ...
Li Wenjing, Li Xueliang, Zhang Jingshu
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An extremal problem on potentially K p,1,1-graphic sequences
Discrete Mathematics & Theoretical Computer Science, 2005 A sequence S is potentially K p,1,1 graphical if it has a realization containing a K p,1,1 as a subgraph, where K p,1,1 is a complete 3-partite graph with partition sizes p,1,1.
Chunhui Lai
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The Product Connectivity Banhatti Index of A Graph
Discussiones Mathematicae Graph Theory, 2019 Let G = (V, E) be a connected graph with vertex set V (G) and edge set E(G). The product connectivity Banhatti index of a graph G is defined as, PB(G)=∑ue1dG(u)dG(e)$PB(G) = \sum\nolimits_{ue} {{1 \over {\sqrt {{d_G}(u){d_G}(e)} }}}$ where ue means that ...
Kulli V.R. +2 more
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Discussiones Mathematicae Graph Theory, 2019 The Turán number of a graph H, denoted by ex(n, H), is the maximum number of edges in any graph on n vertices which does not contain H as a subgraph. Let Pk denote the path on k vertices and let mPk denote m disjoint copies of Pk.
Lan Yongxin, Qin Zhongmei, Shi Yongtang
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On Nordhaus-Gaddum type relations of δ-complement graphs. [PDF]
Heliyon, 2023 Vichitkunakorn P +2 more
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Discussiones Mathematicae Graph Theory, 2018 A digraph is called irregular if its distinct vertices have distinct degree pairs. An irregular digraph is called minimal (maximal) if the removal of any arc (addition of any new arc) results in a non-irregular digraph. It is easily seen that the minimum
Górska Joanna +4 more
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