Results 31 to 40 of about 314 (174)
The Laplacian spread of unicyclic graphs
Applied Mathematics Letters, 2009 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Yan-Hong Bao +2 more
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Ordering graphs with large eccentricity-based topological indices
Journal of Inequalities and Applications, 2021 For a connected graph, the first Zagreb eccentricity index ξ 1 $\xi _{1}$ is defined as the sum of the squares of the eccentricities of all vertices, and the second Zagreb eccentricity index ξ 2 $\xi _{2}$ is defined as the sum of the products of the ...
Yunfang Tang, Xuli Qi
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On Minimum Wiener Polarity Index of Unicyclic Graphs with Prescribed Maximum Degree
Journal of Applied Mathematics, 2014 The Wiener polarity index of a connected graph G is defined as the number of its pairs of vertices that are at distance three. By introducing some graph transformations, in different way with that of Huang et al., 2013, we determine the minimum Wiener ...
Jianping Ou, Xing Feng, Saihua Liu
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Restrained domination in unicyclic graphs
Discussiones Mathematicae Graph Theory, 2009 Let G = (V,E) be a graph. A set S ⊆ V is a restrained dominating set if every vertex in V − S is adjacent to a vertex in S and to a vertex in V − S. The restrained domination number of G, denoted by γr(G), is the minimum cardinality of a restrained dominating set of G. A unicyclic graph is a connected graph that contains precisely one cycle.
Johannes H. Hattingh +4 more
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Locating Eigenvalues of a Symmetric Matrix whose Graph is Unicyclic
Trends in Computational and Applied Mathematics, 2021 We present a linear-time algorithm that computes in a given real interval the number of eigenvalues of any symmetric matrix whose underlying graph is unicyclic.
R. O. Braga +2 more
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On Unicyclic Graphs Spectra: New Results
2016 IEEE Intl Conference on Computational Science and Engineering (CSE) and IEEE Intl Conference on Embedded and Ubiquitous Computing (EUC) and 15th Intl Symposium on Distributed Computing and Applications for Business Engineering (DCABES), 2016 Let G = (V, E) be a unicyclic simple undirected graph. In this paper, we investigate the spectra of a particular class of unicyclic graphs G(q, n1) where q is the size of the unique cycle. Each vertex of the unique cycle is attached to n1 vertices. We provide the " exact values " of the extremal eigenvalues of the adjacency matrix A and the Laplacian ...
Hadji, Makhlouf, Chau, Ming
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The Laplacian Spectral Radius of a Class of Unicyclic Graphs
Journal of Applied Mathematics, 2013 Let C(n,k) be the set of all unicyclic graphs with n vertices and cycle length k. For any U∈C(n,k), U consists of the (unique) cycle (say Ck) of length k and a certain number of trees attached to the vertices of Ck having (in total) n-k edges.
Haixia Zhang
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Unicyclic graphs with equal Laplacian energy [PDF]
Linear and Multilinear Algebra, 2013 11 pages, 11 figures, slightly modified version of Theorem 1 when compared with original ...
Eliseu Fritscher +2 more
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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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