Results 11 to 20 of about 84 (75)
Minimally Strong Subgraph (k,ℓ)-Arc-Connected Digraphs
Discussiones Mathematicae Graph Theory, 2022 Let D = (V,A) be a digraph of order n, S a subset of V of size k and 2 ≤ k ≤ n. A subdigraph H of D is called an S-strong subgraph if H is strong and S ⊆ V (H). Two S-strong subgraphs D1 and D2 are said to be arc-disjoint if A(D1) ∩ A(D2) = ∅.
Sun Yuefang, Jin Zemin
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The Second Neighbourhood for Bipartite Tournaments
Discussiones Mathematicae Graph Theory, 2019 Let T (X ∪ Y, A) be a bipartite tournament with partite sets X, Y and arc set A. For any vertex x ∈ X ∪Y, the second out-neighbourhood N++(x) of x is the set of all vertices with distance 2 from x.
Li Ruijuan, Sheng Bin
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The {−2,−1}-Selfdual and Decomposable Tournaments
Discussiones Mathematicae Graph Theory, 2018 We only consider finite tournaments. The dual of a tournament is obtained by reversing all the arcs. A tournament is selfdual if it is isomorphic to its dual.
Boudabbous Youssef, Ille Pierre
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On the n-Partite Tournaments with Exactly n − m + 1 Cycles of Length m
Discussiones Mathematicae Graph Theory, 2021 Gutin and Rafiey [Multipartite tournaments with small number of cycles, Australas J. Combin. 34 (2006) 17–21] raised the following two problems: (1) Let m ∈ {3, 4, . . ., n}.
Guo Qiaoping, Meng Wei
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Outpaths of Arcs in Regular 3-Partite Tournaments
Discussiones Mathematicae Graph Theory, 2021 Guo [Outpaths in semicomplete multipartite digraphs, Discrete Appl. Math. 95 (1999) 273–277] proposed the concept of the outpath in digraphs. An outpath of a vertex x (an arc xy, respectively) in a digraph is a directed path starting at x (an arc xy ...
Guo Qiaoping, Meng Wei
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Veterinary Dermatology, Volume 27, Issue 5, Page 391-e98, October 2016., 2016 Background– Pseudomonas aeruginosa (PA) may cause suppurative otitis externa with severe inflammation and ulceration in dogs. Multidrug resistance is commonly reported for this organism, creating a difficult therapeutic challenge. Objective– The aim of this study was to evaluate the in vitro antimicrobial activity of a gel containing 0.5 µg/mL of ...
Giovanni Ghibaudo +6 more
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Conditional resolvability in graphs: a survey
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 38, Page 1997-2017, 2004., 2004 For an ordered set W = {w1, w2, …, wk} of vertices and a vertex v in a connected graph G, the code of v with respect to W is the k‐vector cW(v) = (d(v, w1), d(v, w2), …, d(v, wk)), where d(x, y) represents the distance between the vertices x and y. The set W is a resolving set for G if distinct vertices of G have distinct codes with respect to W.
Varaporn Saenpholphat, Ping Zhang
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The hull number of an oriented graph
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 36, Page 2265-2275, 2003., 2003 We present characterizations of connected graphs G of order n ≥ 2 for which h+(G) = n. It is shown that for every two integers n and m with 11≤n−≤m≤(n2), there exists a connected graph G of order n and size m such that for each integer k with 2 ≤ k ≤ n, there exists an orientation of G with hull number G.
Gary Chartrand +2 more
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Classification of Filiform Lie Algebras up to dimension 7 Over Finite Fields
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2016 This paper tries to develop a recent research which consists in using Discrete Mathematics as a tool in the study of the problem of the classification of Lie algebras in general, dealing in this case with filiform Lie algebras up to dimension 7 over ...
Falcón Óscar J. +4 more
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An algebraic framework of weighted directed graphs
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 58, Page 3657-3678, 2003., 2003 We show that an algebraic formulation of weighted directed graphs leads to introducing a k‐vector space equipped with two coproducts Δ and Δ˜ verifying the so‐called coassociativity breaking equation (Δ˜⊗id)Δ=(id⊗Δ)Δ˜. Such a space is called an L‐coalgebra.
Philippe Leroux
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