Affordable Access

Publisher Website

On the out-domination and in-domination numbers of a digraph

Authors
Journal
Discrete Mathematics
0012-365X
Publisher
Elsevier
Publication Date
Identifiers
DOI: 10.1016/s0012-365x(99)90059-6
Keywords
  • Out-Domination
  • In-Domination
  • Digraph

Abstract

Abstract An out-domination set of a digraph D is a set S of vertices of D such that every vertex of D− S is adjacent from some vertex of S. The minimum cardinality of an out-domination set of D is the out-domination number γ +( D). The in-domination number γ −( D) is defined analogously. It is shown that for every digraph D of order n with no isolates, γ −( D)+ γ −( D) ⩽ 4 n/3. Furthermore, the digraphs D for which equality holds are characterized. Other inequalities are also derived.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments

More articles like this

On the domination numbers of generalized de Bruijn...

on Information Processing Letters Jan 01, 2003

The total domination and total bondage numbers of...

on Computers & Mathematics with A... Jan 01, 2007

Total outer-connected domination numbers of trees

on Discrete Applied Mathematics Jan 01, 2009
More articles like this..