Results 41 to 50 of about 106 (86)
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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, 2008 We define the harmonic evolution of states of a graph by iterative application of the harmonic operator (Laplacian over Z2). This provides graphs with a new geometric context and leads to a new tool to analyze them.
Jerzy Kocik
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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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Zero Forcing Sets and Bipartite Circulants
, 2010 In this paper we introduce a class of regular bipartite graphs whose biadja-cency matrices are circulant matrices and we describe some of their properties. Notably, we compute upper and lower bounds for the zero forcing number for such a graph based only
Seth A. Meyer
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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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REPRESENTATIONS OF GRAPHS ON A CYLINDER*
, 2008 . A complete characterization ofthe class ofgraphs that admit a cylindric visibility representation is presented, where vertices are representedby intervals parallel to the axis ofthe cylinderand the edgescorrespond to pairs ofvisible intervals. Moreover,
Ioannis
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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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