Results 11 to 20 of about 337,641 (297)
Eigenspaces for \(-2\) in signed line graphs
The American Journal of CombinatoricsIt is known that \(-2\) appears in the spectrum of a connected signed line graph if and only if its root is either (a) a balanced signed graph, not a tree, that spans a switching of the complete signed graph or (b) an unbalanced simply signed graph ...
Zoran Stanić
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Smarandachely T-Path Step Signed Graphs
, 2010 In this paper, we obtained a characterization of signed graphs whose jump signed graphs are switching equivalent to their two path signed graphs.
Siva Kota Reddy +2 more
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Offensive Alliances in Signed Graphs [PDF]
, 2023 Signed graphs have been introduced to enrich graph structures expressing relationships between persons or general social entities, introducing edge signs to reflect the nature of the relationship, e.g., friendship or enmity. Independently, offensive alliances have been defined and studied for undirected, unsigned graphs.
Zhidan Feng +3 more
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On Singular Signed Graphs with Nullspace Spanned by a Full Vector: Signed Nut Graphs
Discussiones Mathematicae Graph Theory, 2022 A signed graph has edge weights drawn from the set {+1, −1}, and is sign-balanced if it is equivalent to an unsigned graph under the operation of sign switching; otherwise it is sign-unbalanced.
Bašić Nino +3 more
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Signed distance in signed graphs [PDF]
Linear Algebra and its Applications, 2021 Signed graphs have their edges labeled either as positive or negative. Here we introduce two types of signed distance matrix for signed graphs. We characterize balance in signed graphs using these matrices and we obtain explicit formulae for the distance spectrum of some unbalanced signed graphs.
Shahul K. Hameed +4 more
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Ural Mathematical Journal, 2020 In this paper, the study of sum signed graphs is continued. The balancing and switching nature of the graphs are analyzed. The concept of \(rna\) number is revisited and an important relation between the number and its complement is established.
Athira P. Ranjith +1 more
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Negative (and positive) circles in signed graphs: A problem collection
AKCE International Journal of Graphs and Combinatorics, 2018 A signed graph is a graph whose edges are labeled positive or negative. The sign of a circle (cycle, circuit) is the product of the signs of its edges. Most of the essential properties of a signed graph depend on the signs of its circles. Here I describe
Thomas Zaslavsky
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Laplacian integral signed graphs with few cycles
AIMS Mathematics, 2023 A connected graph with n vertices and m edges is called k-cyclic graph if k=m−n+1. We call a signed graph is Laplacian integral if all eigenvalues of its Laplacian matrix are integers.
Dijian Wang, Dongdong Gao
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COMMON-EDGE SIGNED GRAPH OF A SIGNED GRAPH [PDF]
Journal of the Indonesian Mathematical Society, 2010 A Smarandachely k-signed graph (Smarandachely k-marked graph) is anordered pair....DOI : http://dx.doi.org/10.22342/jims.16.2.34.105 ...
P. Siva Kota Reddy +2 more
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Discrete Applied Mathematics, 1982 AbstractA signed graph is a graph with a sign attached to each arc. This article introduces the matroids of signed graphs, which generalize both the polygon matroids and the even-circle (or unoriented cycle) matroids of ordinary graphs. The concepts of balance, switching, restriction and contraction, double covering graphs, and linear representation of
Ghorbani, Ebrahim +3 more
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