On (<i>n, k, l, Δ</i>)-systems
On (<i>n, k, l, Δ</i>)-systems
The paper is devoted to studying one generalization of Steiner systems S ( n , k , l ) closely related to packings and coverings of l -tuples by k -tuples of an n -set. One necessary and one sufficient condition for the existence of such designs are obtained.