Results 1 to 10 of about 6,654 (223)
ON ANTIADJACENCY MATRIX OF A DIGRAPH WITH DIRECTED DIGON(S) [PDF]
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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AKCE International Journal of Graphs and Combinatorics, 2020 Let and be two digraphs; without loops or multiple arcs. An coloring of is a function . We say that is an colored digraph. For an arc of , we say that is the color of over the coloring . A directed path in is an path if is a directed walk in .
Hortensia Galeana-Sánchez +1 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 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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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
Stephan Kreutzer, Sebastian Ordyniak
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On Packing Dijoins in Digraphs and Weighted Digraphs
SIAM Journal on Discrete Mathematics, 2023 Let $D=(V,A)$ be a digraph. A dicut is a cut $δ^+(U)\subseteq A$ for some nonempty proper vertex subset $U$ such that $δ^-(U)=\emptyset$, a dijoin is an arc subset that intersects every dicut at least once, and more generally a $k$-dijoin is an arc subset that intersects every dicut at least $k$ times.
Ahmad Abdi +2 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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The Electronic Journal of Combinatorics, 2011 We study digraphs preserved by a Maltsev operation: Maltsev digraphs. We show that these digraphs retract either onto a directed path or to the disjoint union of directed cycles, showing in this way that the constraint satisfaction problem for Maltsev digraphs is in logspace, L.
Catarina Carvalho +3 more
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