Results 21 to 30 of about 39,748 (262)
Projective-planar signed graphs and tangled signed graphs [PDF]
Journal of Combinatorial Theory, Series B, 2007 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Weak signed Roman domination in graphs [PDF]
Communications in Combinatorics and Optimization, 2020 A weak signed Roman dominating function (WSRDF) of a graph $G$ with vertex set $V(G)$ is defined as a function $f:V(G)\rightarrow\{-1,1,2\}$ having the property that $\sum_{x\in N[v]}f(x)\ge 1$ for each $v\in V(G)$, where $N[v]$ is the closed ...
Lutz Volkmann
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Chromatic Polynomials of Signed Book Graphs
Theory and Applications of Graphs, 2022 For $m \geq 3$ and $n \geq 1$, the $m$-cycle \textit{book graph} $B(m,n)$ consists of $n$ copies of the cycle $C_m$ with one common edge. In this paper, we prove that (a) the number of switching non-isomorphic signed $B(m,n)$ is $n+1$, and (b) the ...
Deepak Sehrawat, Bikash Bhattacharjya
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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 the Aα-Eigenvalues of Signed Graphs
Mathematics, 2021 For α∈[0,1], let Aα(Gσ)=αD(G)+(1−α)A(Gσ), where G is a simple undirected graph, D(G) is the diagonal matrix of its vertex degrees and A(Gσ) is the adjacency matrix of the signed graph Gσ whose underlying graph is G.
Germain Pastén, Oscar Rojo, Luis Medina
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Inertias of Laplacian matrices of weighted signed graphs
Special Matrices, 2019 We study the sets of inertias achieved by Laplacian matrices of weighted signed graphs. First we characterize signed graphs with a unique Laplacian inertia.
Monfared K. Hassani +3 more
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The H-Line Signed Graph Of A Signed Graph
, 2010 For standard terminology and notion in graph theory we refer the reader to Harary; the non-standard will be given in this paper as and when required. We treat only finite simple graphs without self loops and isolates.
Rangarajan, R. +2 more
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On $bullet$-lict signed graphs $L_{bullet_c}(S)$ and $bullet$-line signed graphs $L_bullet(S)$ [PDF]
Transactions on Combinatorics, 2016 A emph{signed graph} (or, in short, emph{sigraph}) $S=(S^u,sigma)$ consists of an underlying graph $S^u :=G=(V,E)$ and a function $sigma:E(S^u)longrightarrow {+,-}$, called the signature of $S$. A emph{marking} of $S$ is a function $mu:V(S)longrightarrow
Mukti Acharya +2 more
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Walks and eigenvalues of signed graphs
Special Matrices, 2023 In this article, we consider the relationships between walks in a signed graph G˙\dot{G} and its eigenvalues, with a particular focus on the largest absolute value of its eigenvalues ρ(G˙)\rho \left(\dot{G}), known as the spectral radius.
Stanić Zoran
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Characterization of Line-Consistent Signed Graphs
Discussiones Mathematicae Graph Theory, 2015 The line graph of a graph with signed edges carries vertex signs. A vertex-signed graph is consistent if every circle (cycle, circuit) has positive vertex-sign product. Acharya, Acharya, and Sinha recently characterized line-consistent signed graphs, i.e.
Slilaty Daniel C., Zaslavsky Thomas
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