Results 61 to 70 of about 157 (114)
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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Remarks on a conjecture about Randic index and graph radius
, 2013 LetG be a nontrivial connected graph. The radiusr.G/ ofG is the minimum eccent- ricity among eccentricities of all vertices in G. The Randiindex of G is defined as R.G/D P uv2E.G/ 1 p d G.u/dG.v/ , and the Harmonic index is defined asH.G/D P uv2E.G/ 2 dG.
T. Dehghan-Zadeh +3 more
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Construction of Albertson Cospectral and Albertson Equienergetic Graphs Using Graph Operations
Journal of Mathematics, Volume 2026, Issue 1, 2026.The energy of a graph is an invariant calculated as the sum of the absolute eigenvalues of its adjacency matrix. This concept extends to various types of energies derived from different graph‐related matrices. This paper explores the spectral properties of Albertson energy and Albertson spectra.
Jane Shonon Cutinha +3 more
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Independent and Vertex Covering Number on Strong Product of Cycles
, 2013 Let α(G) and β(G) be the independent number and vertex covering number, respectively. The strong Product G1 G2 of graph of G1 and G2 has vertex set V (G1 G2 )= V (G1) × V (G2) and edge set E(G1 G2 )= {(u1v1)(u2v2)|[u1u2 ∈ E(G1) and v1v2 ∈ E(G2)] ∪ [u1 ...
Bunjong Kaewwisetkul, T. Sitthiwirattham
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Computational and Mathematical Methods, Volume 2025, Issue 1, 2025.The generalized Mycielskian graphs are known for their advantageous properties employed in interconnection networks in parallel computing to provide efficient and optimized network solutions. This paper focuses on investigating the bounds and computation of the harmonic–arithmetic index of the generalized Mycielskian graph of path graph, cycle graph ...
Pooja Danushri Namidass +2 more
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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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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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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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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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