Results 51 to 60 of about 963 (204)
Journal of Applied Mathematics, 2012 Let Φ(G,λ)=det(λIn-L(G))=∑k=0n(-1)kck(G)λn-k be the characteristic polynomial of the Laplacian matrix of a graph G of order n. In this paper, we give four transforms on graphs that decrease all Laplacian coefficients ck(G) and investigate a conjecture A.
Xinying Pai, Sanyang Liu
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Atom-bond connectivity index and diameter of graphs
Journal of Hebei University of Science and Technology, 2016 For further study of the numerous nice properties of topological indices in physical and chemical fields, it is worth considering the relation between a degree-based index and a distance-based index.
Lin WU, Yumei HU
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The Largest Laplacian Spectral Radius of Unicyclic Graphs with Fixed Diameter
Journal of Applied Mathematics, 2013 We identify graphs with the maximal Laplacian spectral radius among all unicyclic graphs with n vertices and diameter d.
Haixia Zhang
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Zagreb Indices of Trees, Unicyclic and Bicyclic Graphs With Given (Total) Domination
IEEE Access, 2019 Let G = (V, E) be a (molecular) graph. For a family of graphs G, the first Zagreb index M1 and the second Zagreb index M2 have already studied. In particular, it has been presented, the first Zagreb index M1 and the second Zagreb index M2 of trees T in ...
Doost Ali Mojdeh +3 more
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Inequalities for Distance Signless Laplacian Matrix Under Minimum‐Degree Constraints
Journal of Mathematics, Volume 2026, Issue 1, 2026.For a connected graph G of order n, let D(G) denote its distance matrix and let Tr(G) be the diagonal matrix formed by the vertex transmissions. The distance signless Laplacian of G is defined by DQ = D(G) + Tr(G). The largest eigenvalue of DQ, written as ∂1QG, is referred to as the distance signless Laplacian spectral radius of G.
Mohd Abrar Ul Haq +3 more
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On the Absolute Sum of Chromatic Polynomial Coefficient of Graphs
International Journal of Mathematics and Mathematical Sciences, 2011 The absolute sum of chromatic polynomial coefficient of forest, q-tree, unicyclic graphs, and quasiwheel graphs, are determined in this paper.
Shubo Chen
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Maximum Value of the ABC Index of the Edge‐Corona Graph of Two Graphs
Journal of Mathematics, Volume 2026, Issue 1, 2026.This paper is concerned with the atom‐bond connectivity index (ABC index), defined as ABCG=∑uv∈EGdu+dv−2/dudv, where E(G) is the edge set of G and du and dv are degrees of vertices u and v, respectively. G1□G2 denotes the edge‐corona graph of G1 and G2.
Haiqin Liu, Yanling Shao, Pramita Mishra
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Some Results on the Independence Polynomial of Unicyclic Graphs
Discussiones Mathematicae Graph Theory, 2018 Let G be a simple graph on n vertices. An independent set in a graph is a set of pairwise non-adjacent vertices. The independence polynomial of G is the polynomial I(G,x)=∑k=0ns(G,k)xk$I(G,x) = \sum\nolimits_{k = 0}^n {s\left({G,k} \right)x^k }$, where s(
Oboudi Mohammad Reza
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Unicyclic graphs with maximal energy
, 2002 Let G be a graph on n vertices and let λ1,λ2,…,λn be its eigenvalues. The energy of G is defined as E(G)=|λ1|+|λ2|+⋯+|λn|. For various classes of unicyclic graphs, the graphs with maximal energy are determined.
Woo, Ching-Wah +2 more
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Some results on the Laplacian eigenvalues of unicyclic graphs
, 2009 In this paper, we provide the smallest value of the second largest Laplacian eigenvalue for any unicyclic graph, and find the unicyclic graphs attaining that value.
Li, Jianxi +2 more
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