Results 41 to 50 of about 730 (67)
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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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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Graph Classes Generated by Mycielskians
Discussiones Mathematicae Graph Theory, 2020 In this paper we use the classical notion of weak Mycielskian M′(G) of a graph G and the following sequence: M′0(G) = G, M′1(G) = M′(G), and M′n(G) = M′(M′n−1(G)), to show that if G is a complete graph of order p, then the above sequence is a generator ...
Borowiecki Mieczys law +3 more
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Split Euler Tours In 4-Regular Planar Graphs
Discussiones Mathematicae Graph Theory, 2016 The construction of a homing tour is known to be NP-complete. On the other hand, the Euler formula puts su cient restrictions on plane graphs that one should be able to assert the existence of such tours in some cases; in particular we focus on split ...
Couch PJ +3 more
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The Graphs Whose Permanental Polynomials Are Symmetric
Discussiones Mathematicae Graph Theory, 2018 The permanental polynomial π(G,x)=∑i=0nbixn−i$\pi (G,x) = \sum\nolimits_{i = 0}^n {b_i x^{n - i} }$ of a graph G is symmetric if bi = bn−i for each i. In this paper, we characterize the graphs with symmetric permanental polynomials.
Li Wei
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