Results 41 to 50 of about 736 (70)
, 1996 The concept of a line digraph is generalized to that of a directed path graph. The directed path graph $\overrightarrow P_k(D)$ of a digraph D is obtained by representing the directed paths on k vertices of D by vertices.
Broersma, Hajo, Li, Xueliang
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More on the Minimum Size of Graphs with Given Rainbow Index
Discussiones Mathematicae Graph Theory, 2020 The concept of k-rainbow index rxk(G) of a connected graph G, introduced by Chartrand et al., is a natural generalization of the rainbow connection number of a graph.
Zhao Yan
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On the Non-Inverse Graph of a Group
Discussiones Mathematicae - General Algebra and Applications, 2022 Let (G, *) be a finite group and S = {u ∈ G|u ≠ u−1}, then the inverse graph is defined as a graph whose vertices coincide with G such that two distinct vertices u and v are adjacent if and only if either u * v ∈ S or v * u ∈ S.
Amreen Javeria, Naduvath Sudev
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Realizing the chromatic numbers and orders of spinal quadrangulations of surfaces [PDF]
, 2013 A method is suggested for construction of quadrangulations of the closed orientable surface with given genus g and either (1) with given chromatic number or (2) with given order allowed by the genus g. In particular, N. Hartsfield and G. Ringel's results
Lawrencenko, Serge
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Discussiones Mathematicae Graph Theory, 2017 We characterize the class L32$L_3^2 $ of intersection graphs of hypergraphs with rank at most 3 and multiplicity at most 2 by means of a finite list of forbidden induced subgraphs in the class of threshold graphs.
Metelsky Yury +2 more
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(C3, C4, C5, C7)-Free Almost Well-Dominated Graphs
Discussiones Mathematicae Graph Theory, 2022 The domination gap of a graph G is defined as the di erence between the maximum and minimum cardinalities of a minimal dominating set in G. The term well-dominated graphs referring to the graphs with domination gap zero, was first introduced by Finbow et
Alizadeh Hadi +2 more
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Note on structural properties of graphs
Open Mathematics, 2022 In this paper, we establish sufficient and necessary conditions for the existence of abelian subgroups of maximal order of a finite group GG, by means of its commuting graph.
Arreola-Bautista Luis D. +3 more
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Criticality of Switching Classes of Reversible 2-Structures Labeled by an Abelian Group
Discussiones Mathematicae Graph Theory, 2017 Let V be a finite vertex set and let (𝔸, +) be a finite abelian group. An 𝔸-labeled and reversible 2-structure defined on V is a function g : (V × V) \ {(v, v) : v ∈ V } → 𝔸 such that for distinct u, v ∈ V, g(u, v) = −g(v, u).
Belkhechine Houmem +2 more
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Conflict-Free Vertex-Connections of Graphs
Discussiones Mathematicae Graph Theory, 2020 A path in a vertex-colored graph is called conflict-free if there is a color used on exactly one of its vertices. A vertex-colored graph is said to be conflict-free vertex-connected if any two vertices of the graph are connected by a conflict-free path ...
Li Xueliang +5 more
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Requiring that Minimal Separators Induce Complete Multipartite Subgraphs
Discussiones Mathematicae Graph Theory, 2018 Complete multipartite graphs range from complete graphs (with every partite set a singleton) to edgeless graphs (with a unique partite set). Requiring minimal separators to all induce one or the other of these extremes characterizes, respectively, the ...
McKee Terry A.
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