## Abstract A vertex set __X__ of a digraph __D__β=β(__V, A__) is a __kernel__ if __X__ is independent (i.e., all pairs of distinct vertices of __X__ are nonβadjacent) and for every __v__ β __V__β__X__ there exists __x__ β __X__ such that __vx__ β __A__. A vertex set __X__ of a digraph __D__β=β(__V
On the Capacity of Digraphs
β Scribed by Noga Alon
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 76 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0195-6698
No coin nor oath required. For personal study only.
β¦ Synopsis
For a digraph G = (V, E) let w(G n ) denote the maximum possible cardinality of a subset S of V n in which for every ordered pair
It is also shown that for every n there is a tournament T on 2n vertices whose capacity is at least β n, whereas the maximum number of vertices in a transitive subtournament in it is only O(log n). This settles a question of KΓΆrner and Simonyi.
π SIMILAR VOLUMES
## Abstract If every three circuits of a digraph have a common vertex, then all the circuits have one.
We say that a digraph D has the odd cycle property if there exists an edge subset S such that every cycle of D has an odd number of edges from S. We give necessary and sufficient conditions for a digraph to have the odd cycle property. We also consider the analogous problem for graphs.
It has been proved that if the diameter D of a digraph G satisfies D Υ 2α Οͺ 2, where α is a parameter which can be thought of as a generalization of the girth of a graph, then G is superconnected. Analogously, if D Υ 2α Οͺ 1, then G is edge-superconnected. In this paper, we studied some similar condi
Recently, it was proved that if the diameter D of a graph G is small enough in comparison with its girth, then G is maximally connected and that a similar result also holds for digraphs. More precisely, if the diameter D of a digraph G satisfies D 5 21 -1, then G has maximum connectivity ( K = 6 ) .