Results 41 to 50 of about 834 (84)
Arc-Disjoint Hamiltonian Cycles in Round Decomposable Locally Semicomplete Digraphs
Discussiones Mathematicae Graph Theory, 2018 Let D = (V,A) be a digraph; if there is at least one arc between every pair of distinct vertices of D, then D is a semicomplete digraph. A digraph D is locally semicomplete if for every vertex x, the out-neighbours of x induce a semicomplete digraph and ...
Li Ruijuan, Han Tingting
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Arc-Disjoint Hamiltonian Paths in Strong Round Decomposable Local Tournaments
Discussiones Mathematicae Graph Theory, 2021 Thomassen, [Edge-disjoint Hamiltonian paths and cycles in tournaments, J. Combin. Theory Ser. B 28 (1980) 142–163] proved that every strong tournament has a pair of arc-disjoint Hamiltonian paths with distinct initial vertices and distinct terminal ...
Meng Wei
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A digraph equation for homomorphic images
International Journal of Mathematics and Mathematical Sciences, Volume 9, Issue 2, Page 409-411, 1986., 1986 The definitions of a homomorphism and a contraction of a graph are generalized to digraphs. Solutions are given to the graph equation .
Robert D. Girse, Richard A. Gillman
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A Note on Roman Domination of Digraphs
Discussiones Mathematicae Graph Theory, 2019 A vertex subset S of a digraph D is called a dominating set of D if every vertex not in S is adjacent from at least one vertex in S. The domination number of a digraph D, denoted by γ(D), is the minimum cardinality of a dominating set of D.
Chen Xiaodan, Hao Guoliang, Xie Zhihong
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The Double Roman Domatic Number of a Digraph
Discussiones Mathematicae Graph Theory, 2020 A double Roman dominating function on a digraph D with vertex set V (D) is defined in [G. Hao, X. Chen and L. Volkmann, Double Roman domination in digraphs, Bull. Malays. Math. Sci. Soc. (2017).] as a function f : V (D) → {0, 1, 2, 3} having the property
Volkmann Lutz
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Sufficient Conditions for a Digraph to Admit A (1, ≤ ℓ)-Identifying Code
Discussiones Mathematicae Graph Theory, 2021 A (1, ≤ ℓ)-identifying code in a digraph D is a subset C of vertices of D such that all distinct subsets of vertices of cardinality at most ℓ have distinct closed in-neighbourhoods within C. In this paper, we give some sufficient conditions for a digraph
Balbuena Camino +2 more
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Linear versus set valued Kronecker representations
, 2016 A set valued representation of the Kronecker quiver is nothing but a quiver. We apply the forgetful functor from vector spaces to sets and compare linear with set valued representations of the Kronecker quiver.Comment: 7 ...
Großblotekamp, Kay, Krause, Henning
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A note on directed 4-cycles in digraphs [PDF]
, 2012 Using some combinatorial techniques, in this note, it is proved that if $\alpha\geq 0.28866$, then any digraph on $n$ vertices with minimum outdegree at least $\alpha n$ contains a directed cycle of length at most ...
Liang, Hao, Xu, Jun-Ming
core
, 2012 The competition graph of a digraph $D$ is a (simple undirected) graph which has the same vertex set as $D$ and has an edge between two distinct vertices $x$ and $y$ if and only if there exists a vertex $v$ in $D$ such that $(x,v)$ and $(y,v)$ are arcs of
Boram Park +8 more
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On characteristic and permanent polynomials of a matrix
Special Matrices, 2017 There is a digraph corresponding to every square matrix over ℂ. We generate a recurrence relation using the Laplace expansion to calculate the characteristic and the permanent polynomials of a square matrix.
Singh Ranveer, Bapat R. B.
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