Results 31 to 40 of about 68 (57)
On Well-Covered Direct Products
Discussiones Mathematicae Graph Theory, 2022 A graph G is well-covered if all maximal independent sets of G have the same cardinality. In 1992 Topp and Volkmann investigated the structure of well-covered graphs that have nontrivial factorizations with respect to some of the standard graph products.
Kuenzel Kirsti, Rall Douglas F.
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Cyclic Cordial Labeling for the Lemniscate Graphs and Their Second Powers
Journal of Mathematics, Volume 2025, Issue 1, 2025.A lemniscate graph, usually denoted by Ln,m, is defined as a union of two cycles Cn and Cm that share a common vertex. A simple graph is called cyclic group cordial if we can provide a three elements’ cyclic group labeling satisfying certain conditions.
M. A. AbdAllah +4 more
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Improving the Efficiency of Fuzzy Graphs and Their Complements Using Some Influencing Parameters
Journal of Mathematics, Volume 2025, Issue 1, 2025.This study focuses on constructing optimal network structures for fuzzy graph (FG) products. In graph theory, the complement of a FG product is essential since it analyses alternate interactions between the vertices. Such a complement is used to represent situations in which specific connections are deliberately excluded, which helps to understand ...
A. Meenakshi +4 more
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(Open) packing number of some graph products [PDF]
Discrete Mathematics & Theoretical Computer Science, 2020 The packing number of a graph $G$ is the maximum number of closed neighborhoods of vertices in $G$ with pairwise empty intersections. Similarly, the open packing number of $G$ is the maximum number of open neighborhoods in $G$ with pairwise empty ...
Doost Ali Mojdeh +3 more
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Some Observations on the Smallest Adjacency Eigenvalue of a Graph
Discussiones Mathematicae Graph Theory, 2020 In this paper, we discuss various connections between the smallest eigenvalue of the adjacency matrix of a graph and its structure. There are several techniques for obtaining upper bounds on the smallest eigenvalue, and some of them are based on Rayleigh
Cioabă Sebastian M. +2 more
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The Vertex-Rainbow Connection Number of Some Graph Operations
Discussiones Mathematicae Graph Theory, 2021 A path in an edge-colored (respectively vertex-colored) graph G is rainbow (respectively vertex-rainbow) if no two edges (respectively internal vertices) of the path are colored the same.
Li Hengzhe, Ma Yingbin, Li Xueliang
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Products Of Digraphs And Their Competition Graphs
Discussiones Mathematicae Graph Theory, 2016 If D = (V, A) is a digraph, its competition graph (with loops) CGl(D) has the vertex set V and {u, v} ⊆ V is an edge of CGl(D) if and only if there is a vertex w ∈ V such that (u, w), (v, w) ∈ A.
Sonntag Martin, Teichert Hanns-Martin
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About (k, l)-Kernels, Semikernels and Grundy Functions in Partial Line Digraphs
Discussiones Mathematicae Graph Theory, 2019 Let D be a digraph of minimum in-degree at least 1. We prove that for any two natural numbers k, l such that 1 ≤ l ≤ k, the number of (k, l)-kernels of D is less than or equal to the number of (k, l)-kernels of any partial line digraph ℒD. Moreover, if l
Balbuena C. +2 more
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Eigenvalues of complex unit gain graphs and gain regularity
Special MatricesA complex unit gain graph (or T{\mathbb{T}}-gain graph) Γ=(G,γ)\Gamma =\left(G,\gamma ) is a gain graph with gains in T{\mathbb{T}}, the multiplicative group of complex units.
Brunetti Maurizio
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Dualizing Distance-Hereditary Graphs
Discussiones Mathematicae Graph Theory, 2021 Distance-hereditary graphs can be characterized by every cycle of length at least 5 having crossing chords. This makes distance-hereditary graphs susceptible to dualizing, using the common extension of geometric face/vertex planar graph duality to cycle ...
McKee Terry A.
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