Results 1 to 10 of about 390,128 (262)
Bounds on the connectivity of iterated line graphs
Electronic Journal of Graph Theory and Applications, 2022 For simple connected graphs that are neither paths nor cycles, we define l(G)=max{m : G has a divalent path of length m that is not both of length 2 and in a K3}, where a divalent path is a path whose internal vertices have degree two in G.
Yehong Shao
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Axioms, 2022 The Randić index of a graph G, denoted by R(G), is defined as the sum of 1/d(u)d(v) for all edges uv of G, where d(u) denotes the degree of a vertex u in G. In this note, we show that R(L(T))>n4 for any tree T of order n≥3.
Jiangfu Zhang, Baoyindureng Wu
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Incidence matrices and line graphs of mixed graphs
Special Matrices, 2023 In the theory of line graphs of undirected graphs, there exists an important theorem linking the incidence matrix of the root graph to the adjacency matrix of its line graph. For directed or mixed graphs, however, there exists no analogous result.
Abudayah Mohammad +2 more
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Outerplanarity of line graphs and iterated line graphs
Applied Mathematics Letters, 2011 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Lin, Huiqiu +3 more
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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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On the Representability of Line Graphs [PDF]
, 2011 10 pages, 5 ...
Sergey Kitaev +3 more
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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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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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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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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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