Artículos de revistas
On the L(2,1)-labeling of block graphs
Fecha
2011-02Registro en:
Bonomo, Flavia; Cerioli, Marcia R.; On the L(2,1)-labeling of block graphs; Taylor & Francis Ltd; International Journal Of Computer Mathematics; 88; 3; 2-2011; 468-475
0020-7160
Autor
Bonomo, Flavia
Cerioli, Marcia R.
Resumen
The distance-two labelling problem of graphs was proposed by Griggs and Roberts in 1988, and it is a variation of the frequency assignment problem introduced by Hale in 1980. An L(2, 1)-labelling of a graph G is an assignment of non-negative integers to the vertices of G such that vertices at distance two receive different numbers and adjacent vertices receive different and non-consecutive integers. The L(2, 1)-labelling number of G, denoted by λ(G), is the smallest integer k such that G has a L(2, 1)-labelling in which no label is greater than k.