Results 61 to 70 of about 168 (131)
Discussiones Mathematicae Graph Theory, 2019 The Turán number of a graph H, denoted by ex(n, H), is the maximum number of edges in any graph on n vertices which does not contain H as a subgraph. Let Pk denote the path on k vertices and let mPk denote m disjoint copies of Pk.
Lan Yongxin, Qin Zhongmei, Shi Yongtang
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On the diameters of friends-and-strangers graphs [PDF]
Given simple graphs \(X\) and \(Y\) on the same number of vertices, the friends-and-strangers graph \(\operatorname{FS}(X, Y)\) has as its vertices all bijections from \(V(X)\) to \(V(Y)\), where two bijections are adjacent if and only if they differ on ...
Jeong, Ryan
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On Nordhaus-Gaddum type relations of δ-complement graphs. [PDF]
Heliyon, 2023 Vichitkunakorn P +2 more
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Discussiones Mathematicae Graph Theory, 2018 A digraph is called irregular if its distinct vertices have distinct degree pairs. An irregular digraph is called minimal (maximal) if the removal of any arc (addition of any new arc) results in a non-irregular digraph. It is easily seen that the minimum
Górska Joanna +4 more
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An efficient asymmetric removal lemma and its limitations
Forum of Mathematics, SigmaThe triangle removal states that if G contains $\varepsilon n^2$ edge-disjoint triangles, then G contains $\delta (\varepsilon )n^3$ triangles. Unfortunately, there are no sensible bounds on the order of growth of $\delta (\varepsilon )$
Lior Gishboliner +2 more
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Anti-Ramsey Number of Hanoi Graphs
Discussiones Mathematicae Graph Theory, 2019 Let ar(G,H) be the largest number of colors such that there exists an edge coloring of G with ar(G,H) colors such that each subgraph isomorphic to H has at least two edges in the same color. We call ar(G,H) the anti- Ramsey number for a pair of graphs (G,
Gorgol Izolda, Lechowska Anna
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Erdős-Gallai-Type Results for Total Monochromatic Connection of Graphs
Discussiones Mathematicae Graph Theory, 2019 A graph is said to be total-colored if all the edges and the vertices of the graph are colored. A total-coloring of a graph is a total monochromatically-connecting coloring (TMC-coloring, for short) if any two vertices of the graph are connected by a ...
Jiang Hui, Li Xueliang, Zhang Yingying
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Graph with extremal connectivity index
, 2008 . Let G be a graph and δv the degree of its vertex v. The connectivity index of G is χ = (δu δv) −1/2, with the summation ranging over all pairs of adjacent vertices of G.
Ljiljana Pavlović, Ivan Gutman
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Conflict-free coloring of graphs
, 2013 We study the conflict-free chromatic number χCF of graphs from ex-tremal and probabilistic point of view. We resolve a question of Pach and Tardos about the maximum conflict-free chromatic number an n-vertex graph can have. Our construction is randomized.
Tibor Szabó +2 more
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Inverse Problem on the Steiner Wiener Index
Discussiones Mathematicae Graph Theory, 2018 The Wiener index W(G) of a connected graph G, introduced by Wiener in 1947, is defined as W(G) =∑u,v∈V (G)dG(u, v), where dG(u, v) is the distance (the length a shortest path) between the vertices u and v in G. For S ⊆ V (G), the Steiner distance d(S) of
Li Xueliang, Mao Yaping, Gutman Ivan
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