Results 21 to 30 of about 4,935,854 (284)
Journal of Combinatorial Theory, Series B, 2018 The treewidth of a graph is an important invariant in structural and algorithmic graph theory. This paper studies the treewidth of line graphs. We show that determining the treewidth of the line graph of a graph $G$ is equivalent to determining the minimum vertex congestion of an embedding of $G$ into a tree.
Daniel J. Harvey, David R. Wood
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Line game-perfect graphs [PDF]
Discrete Mathematics & Theoretical Computer ScienceThe $[X,Y]$-edge colouring game is played with a set of $k$ colours on a graph $G$ with initially uncoloured edges by two players, Alice (A) and Bob (B). The players move alternately. Player $X\in\{A,B\}$ has the first move. $Y\in\{A,B,-\}$.
Stephan Dominique Andres, Wai Lam Fong
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On Edge Fuzzy Line Graphs and their Fuzzy Congraphs [PDF]
Control and Optimization in Applied Mathematics, 2021 In this paper, we introduce some new concepts of fuzzy graphs with the notion of degree of an edge in fuzzy line graphs and congraphs. Also, some properties and some lemmas of edge fuzzy line graphs and congraphs are studied.
Siyamak Firouzian +2 more
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On Automorphisms of Line-graphs
European Journal of Combinatorics, 1980 This paper generalizes some results on hypergraph reconstruction due to \textit{C. Berge} [C. R. Acad. Sci., Paris, Ser. A 274, 1783-1786 (1972; Zbl 0236.05129)] and \textit{J.C.Fournier} [Proc. 1rst Working Sem. Hypergraphs, Columbus 1972, Lecture Notes Math. 411, 95-98 (1974; Zbl 0302.05113)].
Péter L. Erdös, Zoltán Füredi
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Electronic Notes in Discrete Mathematics, 2010 Abstract We observe that ω ( G ) + χ ( S ( G → ) ) = n = ω ( S ( G → ) ) + χ ( G ) for any graph G with n vertices, where G → is any acyclic orientation of G and where S ( G → ) is the (complement of the) auxiliary line graph introduced in [Cornaz, D., and Jost, V., A one-to-one ...
Cornaz, Denis, Meurdesoif, Philippe
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The gamma-Signless Laplacian Adjacency Matrix of Mixed Graphs
Theory and Applications of Graphs, 2023 The α-Hermitian adjacency matrix Hα of a mixed graph X has been recently introduced. It is a generalization of the adjacency matrix of unoriented graphs. In this paper, we consider a special case of the complex number α.
Omar Alomari +2 more
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Discrete Mathematics, 2011 Boxicity of a graph H, denoted by box(H), is the minimum integer k such that H is an intersection graph of axis-parallel k-dimensional boxes in R^k. In this paper, we show that for a line graph G of a multigraph, box(G) <= 2Δ(\lceil log_2(log_2(Δ)) \rceil + 3) + 1, where Δdenotes the maximum degree of G.
L. Sunil Chandran +2 more
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Virtual Haptic Exploratory Visualization of Line Graphs and Charts [PDF]
, 2002 This paper describes ongoing research investigating how visualizations, especially line-graphs and charts, may be represented by haptics both to understand the structure and the values associated with the graphical realization.
Jonathan C. Roberts +5 more
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Encapsulation structure and dynamics in hypergraphs
Journal of Physics: Complexity, 2023 Hypergraphs have emerged as a powerful modeling framework to represent systems with multiway interactions, that is systems where interactions may involve an arbitrary number of agents. Here we explore the properties of real-world hypergraphs, focusing on
Timothy LaRock, Renaud Lambiotte
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Graph equations for line graphs and total graphs
Discrete Mathematics, 1975 AbstractAll pairs (G,H) of graphs G,H satisfying L(G) = T(H) are determined. The “graph equation“ L(G)= T(H) is also solved.
Dragos M. Cvetkovic, Slobodan K. Simic
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