Results 51 to 60 of about 808 (83)
The Cayley Sum Graph of Ideals of a Lattice
Discussiones Mathematicae - General Algebra and Applications, 2020 Let L be a lattice, 𝒥(L) be the set of ideals of L and S be a subset of 𝒥 (L). In this paper, we introduce an undirected Cayley graph of L, denoted by ΓL,S with elements of 𝒥 (L) as the vertex set and, for two distinct vertices I and J, I is adjacent to ...
Afkhami Mojgan +2 more
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Rings whose total graphs have genus at most one [PDF]
, 2010 Let $R$ be a commutative ring with $\Z(R)$ its set of zero-divisors. In this paper, we study the total graph of $R$, denoted by $\T(\Gamma(R))$. It is the (undirected) graph with all elements of $R$ as vertices, and for distinct $x, y\in R$, the vertices
Maimani, Hamid Reza +2 more
core
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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Bipartite graphs with close domination and k-domination numbers
Open Mathematics, 2020 Let kk be a positive integer and let GG be a graph with vertex set V(G)V(G). A subset D⊆V(G)D\subseteq V(G) is a kk-dominating set if every vertex outside DD is adjacent to at least kk vertices in DD. The kk-domination number γk(G){\gamma }_{k}(G) is the
Ekinci Gülnaz Boruzanlı +1 more
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Spectra of Orders for k-Regular Graphs of Girth g
Discussiones Mathematicae Graph Theory, 2021 A (k, g)-graph is a k-regular graph of girth g. Given k ≥ 2 and g ≥ 3, infinitely many (k, g)-graphs of infinitely many orders are known to exist. Our goal, for given k and g, is the classification of all orders n for which a (k, g)-graph of order n ...
Jajcay Robert, Raiman Tom
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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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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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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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On J-colorability of certain derived graph classes
Acta Universitatis Sapientiae: Informatica, 2019 A vertex v of a given graph G is said to be in a rainbow neighbourhood of G, with respect to a proper coloring C of G, if the closed neighbourhood N[v] of the vertex v consists of at least one vertex from every color class of G with respect to C.
Fornasiero Federico, Naduvath Sudev
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Heuristic method to determine lucky k-polynomials for k-colorable graphs
Acta Universitatis Sapientiae: Informatica, 2019 The existence of edges is a huge challenge with regards to determining lucky k-polynomials of simple connected graphs in general. In this paper the lucky 3-polynomials of path and cycle graphs of order, 3 ≤ n ≤ 8 are presented as the basis for the ...
Kok Johan
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