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Skew-signings of positive weighted digraphs
Arab Journal of Mathematical Sciences, 2018 An arc-weighted digraph is a pair (D , ω) where D is a digraph and ω is an arc-weight function that assigns to each arc u v of D a nonzero real number ω (u v) .
Kawtar Attas +2 more
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Enumeration of cyclic vertices and components over the congruence a¹¹ ≡ b (mod n) [PDF]
Notes on Number Theory and Discrete Mathematics, 2023 For each positive integer n, we assign a digraph Γ(n,11) whose set of vertices is Zₙ={0,1,2,...,n-1} and there exists exactly one directed edge from the vertex a to the vertex b iff a¹¹ ≡ b (mod n).
Sanjay Kumar Thakur +2 more
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The majority coloring of the join and Cartesian product of some digraph [PDF]
MATEC Web of Conferences, 2022 A majority coloring of a digraph is a vertex coloring such that for every vertex, the number of vertices with the same color in the out-neighborhood does not exceed half of its out-degree.
Shi Mei +3 more
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ON ANTIADJACENCY MATRIX OF A DIGRAPH WITH DIRECTED DIGON(S)
Barekeng, 2022 The antiadjacency matrix is one representation matrix of a digraph. In this paper, we find the determinant and the characteristic polynomial of the antiadjacency matrix of a digraph with directed digon(s).
Muhammad Irfan Arsyad Prayitno +1 more
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On Characteristic Polynomial of Antiadjacency Matrix of A Line Digraph
Jurnal Matematika UNAND, 2022 In this paper, we find the characteristic polynomial of the antiadjacency matrix of a line digraph. There are recent studies on the relation between the characteristic polynomial of the adjacency matrix and its line digraph, we are also interested in ...
Muhammad Irfan Arsyad Prayitno +1 more
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Kernel perfect and critical kernel imperfect digraphs structure [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 A kernel $N$ of a digraph $D$ is an independent set of vertices of $D$ such that for every $w \in V(D)-N$ there exists an arc from $w$ to $N$. If every induced subdigraph of $D$ has a kernel, $D$ is said to be a kernel perfect digraph. Minimal non-kernel
Hortensia Galeana-Sánchez +1 more
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H-kernels by walks in an () digraph
AKCE International Journal of Graphs and Combinatorics, 2019 Let be a digraph possibly with loops and a digraph without loops whose arcs are colored with the vertices of ( is said to be an -colored digraph). A directed walk in is said to be an -walk if and only if the consecutive colors encountered on form a ...
Hortensia Galeana-Sánchez +3 more
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Journal of Combinatorial Theory, Series B, 2017 An antidirected trail in a digraph is a trail (a walk with no arc repeated) in which the arcs alternate between forward and backward arcs. An antidirected path is an antidirected trail where no vertex is repeated. We show that it is NP-complete to decide whether two vertices $x,y$ in a digraph are connected by an antidirected path, while one can decide
Bang-Jensen, Jørgen +3 more
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Digraph Decompositions and Monotonicity in Digraph Searching [PDF]
Theoretical Computer Science, 2008 We consider monotonicity problems for graph searching games. Variants of these games - defined by the type of moves allowed for the players - have been found to be closely connected to graph decompositions and associated width measures such as path- or tree-width. Of particular interest is the question whether these games are monotone, i.e. whether the
Kreutzer, S, Ordyniak, S
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