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Some Remarks On The Structure Of Strong K-Transitive Digraphs
Discussiones Mathematicae Graph Theory, 2014 A digraph D is k-transitive if the existence of a directed path (v0, v1, . . . , vk), of length k implies that (v0, vk) ∈ A(D). Clearly, a 2-transitive digraph is a transitive digraph in the usual sense.
Hernández-Cruz César +1 more
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(K − 1)-Kernels In Strong K-Transitive Digraphs
Discussiones Mathematicae Graph Theory, 2015 Let D = (V (D),A(D)) be a digraph and k ≥ 2 be an integer. A subset N of V (D) is k-independent if for every pair of vertices u, v ∈ N, we have d(u, v) ≥ k; it is l-absorbent if for every u ∈ V (D) − N, there exists v ∈ N such that d(u, v) ≤ l.
Wang Ruixia
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Hamiltonian Cycle Problem in Strong k-Quasi-Transitive Digraphs With Large Diameter
Discussiones Mathematicae Graph Theory, 2021 Let k be an integer with k ≥ 2. A digraph is k-quasi-transitive, if for any path x0x1... xk of length k, x0 and xk are adjacent. Let D be a strong k-quasi-transitive digraph with even k ≥ 4 and diameter at least k +2.
Wang Ruixia
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Relational Galois connections between transitive fuzzy digraphs [PDF]
, 2020 Fuzzy-directed graphs are often chosen as the data structure to model and implement solutions to several problems in the applied sciences. Galois connections have also shown to be useful both in theoretical and in practical problems.
Cabrera, Inma P. +4 more
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Disimplicial arcs, transitive vertices, and disimplicial eliminations [PDF]
, 2014 In this article we deal with the problems of finding the disimplicial arcs of a digraph and recognizing some interesting graph classes defined by their existence.
Eguía, Martiniano +1 more
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Subdegree growth rates of infinite primitive permutation groups [PDF]
, 2006 A transitive group $G$ of permutations of a set $\Omega$ is primitive if the only $G$-invariant equivalence relations on $\Omega$ are the trivial and universal relations.
Smith, Simon M.
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Some Results on 4-Transitive Digraphs
Discussiones Mathematicae Graph Theory, 2017 Let D be a digraph with set of vertices V and set of arcs A. We say that D is k-transitive if for every pair of vertices u, v ∈ V, the existence of a uv-path of length k in D implies that (u, v) ∈ A.
García-Vázquez Patricio Ricardo +1 more
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Cycles and transitivity by monochromatic paths in arc-coloured digraphs
AKCE International Journal of Graphs and Combinatorics, 2015 A digraph D is an m-coloured digraph if its arcs are coloured with m colours. If D is an m-coloured digraph and a∈A(D), then colour(a) will denote the colour has been used on a.
Enrique Casas-Bautista +2 more
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4-Transitive Digraphs I: The Structure of Strong 4-Transitive Digraphs
Discussiones Mathematicae Graph Theory, 2013 Let D be a digraph, V (D) and A(D) will denote the sets of vertices and arcs of D, respectively. A digraph D is transitive if for every three distinct vertices u, v,w ∈ V (D), (u, v), (v,w) ∈ A(D) implies that (u,w) ∈ A(D).
Hernández-Cruz César
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(A, ℬ)-kernels and Sands, Sauer and Woodrow’s theorem
AKCE International Journal of Graphs and Combinatorics, 2019 Let D = (V(D), A(D)) a digraph. Consider the set PD= {P : P is a non trivial finite directed path in D} and let A and ℬ two subsets of PD. A subset N of V(D) is said to be an (A, ℬ)-kernel of D if (1) for every subset {u, v} of N there exists no uv ...
Hortensia Galeana-Sánchez +2 more
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