Results 21 to 30 of about 337,641 (297)
Signed graphs connected with the root lattice
Bibechana, 2014 For any base of the root lattice (An) we can construct a signed graph. A signed graph is one whose edges are signed by +1 or -1. A signed graph is balanced if and only if its vertex set can be divided into two sets-either of which may be empty–so that ...
RN Yadav
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Edge coloring signed graphs [PDF]
Discrete Mathematics, 2020 We define a method for edge coloring signed graphs and what it means for such a coloring to be proper. Our method has many desirable properties: it specializes to the usual notion of edge coloring when the signed graph is all-negative, it has a natural definition in terms of vertex coloring of a line graph, and the minimum number of colors required for
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Signed distance Laplacian matrices for signed graphs
Linear and Multilinear Algebra, 2022 A signed graph is a graph whose edges are labeled either positive or negative. Corresponding to the two signed distance matrices defined for signed graphs, we define two signed distance laplacian matrices. We characterize balance in signed graphs using these matrices and find signed distance laplacian spectra of some classes of unbalanced signed graphs.
Roshni T. Roy +3 more
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The Nullity of Bicyclic Signed Graphs [PDF]
, 2012 Let \Gamma be a signed graph and let A(\Gamma) be the adjacency matrix of \Gamma. The nullity of \Gamma is the multiplicity of eigenvalue zero in the spectrum of A(\Gamma).
Cheng B +7 more
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SIGNED GENERALIZED PETERSEN GRAPH AND ITS CHARACTERISTIC POLYNOMIAL [PDF]
Journal of Algebraic Systems, 2018 Let G^s be a signed graph, where G = (V;E) is the underlying simple graph and s : E(G) to {+, -} is the sign function on E(G). In this paper, we obtain k-th signed spectral moment and k-th signed Laplacian spectral moment of Gs together with coefficients ...
E. Ghasemian, Gh. H. Fath-Tabar
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Total Minimal Dominating Signed Graph [PDF]
, 2010 Cartwright and Harary considered graphs in which vertices represent persons and the edges represent symmetric dyadic relations amongst persons each of which designated as being positive or negative according to whether the nature of the relationship is ...
Reddy, Siva Kota, Vijay, S.
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Coloring problem of signed interval graphs [PDF]
Transactions on Combinatorics, 2019 A signed graph $(G,\sigma)$ is a graph together with an assignment of signs $\{+,-\}$ to its edges where $\sigma$ is the subset of its negative edges.
Farzaneh Ramezani
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On net-Laplacian energy of signed graphs
Communications in Combinatorics and Optimization, 2017 A signed graph is a graph where the edges are assigned either positive or negative signs. Net degree of a signed graph is the difference between the number of positive and negative edges incident with a vertex. It is said to be net-regular if all its
Nutan G. Nayak
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On Laplacian Equienergetic Signed Graphs [PDF]
Journal of Mathematics, 2021 The Laplacian energy of a signed graph is defined as the sum of the distance of its Laplacian eigenvalues from its average degree. Two signed graphs of the same order are said to be Laplacian equienergetic if their Laplacian energies are equal. In this paper, we present several infinite families of Laplacian equienergetic signed graphs.
Qingyun Tao, Lixin Tao
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A bivariate chromatic polynomial for signed graphs [PDF]
, 2014 We study Dohmen--P\"onitz--Tittmann's bivariate chromatic polynomial $c_\Gamma(k,l)$ which counts all $(k+l)$-colorings of a graph $\Gamma$ such that adjacent vertices get different colors if they are $\le k$.
Beck, Matthias, Hardin, Mela
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