%0 Journal Article 
%A Cabrera Martínez, Abel
%A Kuziak, Dorota
%A González Yero, Ismael
%T A constructive characterization of vertex cover Roman trees
%D 2020
%@ 1234-3099

%U http://hdl.handle.net/10498/24150
%X A Roman dominating function on a graph G = (V (G), E (G)) is a function f : V (G) -> {0, 1, 2} satisfying the condition that every vertex u for which f (u) = 0 is adjacent to at least one vertex v for which f (v) = 2. The Roman dominating function f is an outer-independent Roman dominating function on G if the set of vertices labeled with zero under f is an independent set. The outer-independent Roman domination number gamma(oiR) (G) is the minimum weight w(f ) = Sigma(v is an element of V), ((G)) f(v) of any outer-independent Roman dominating function f of G. A vertex cover of a graph G is a set of vertices that covers all the edges of G. The minimum cardinality of a vertex cover is denoted by alpha(G). A graph G is a vertex cover Roman graph if gamma(oiR) (G) = 2 alpha(G). A constructive characterization of the vertex cover Roman trees is given in this article.
%K Roman domination
%K outer-independent Roman domination
%K vertex cover
%K vertex independence
%K trees
%~ Universidad de Cádiz