  Our work becomes integrated into the general problem of the stability of the
network ad hoc. Some, works attacked this problem. Among these works, we find
the modelling of the network ad hoc in the form of a graph. Thus the problem of
stability of the network ad hoc which corresponds to a problem of allocation of
frequency amounts to a problem of allocation of colors in the vertex of graph.
we present use a parameter of coloring the number of Grundy. The Grundy number
of a graph G, denoted by (G), is the largest k such that G has a greedy
k-coloring, that is a coloring with colours obtained by applying the greedy
algorithm according to some ordering of the vertices of G. In this paper, we
study the Grundy number of the lexicographic, Cartesian and direct products of
two graphs in terms of the Grundy numbers of these graphs.
