A directed covering design, DC(v, k, λ), is a (v, k, 2λ) covering design in which the blocks are regarded as ordered k-tuples and in which each ordered pair of elements occurs in at least λ blocks. Let DE(v, k, λ) denote the minimum number of blocks in a DC(v, k, λ). In this paper the values of the function DE(v, 5, λ) are determined for all even integers v ≥ 5 and λ odd.
|Number of pages||22|
|Journal||Australasian Journal of Combinatorics|
|State||Published - 2003|