| Popis: |
A pair (X, B) will be a t-wise balanced design (tBD) of type t−(v, K, λ) if B = (Bi: i ϵ I) is a family of subsets of X, called blocks, such that: (i) |X| = v ϵ N, where N is the set of positive integers; (ii) 1⩽t⩽|Bi|ϵK⊆N, for every i ϵ I; and (iii) if T ⊆ X, |T| = t, then there are λ ϵ N indices i ϵ I where T ⊆ Bi. Throughout this paper we make three restrictions on our tBD's: (1) there are no repeated blocks, i.e. B will be a set of subsets of X; (2) t ∉ K or there are no blocks of size t; and (3) Pk(X)⊈B or B does not contain all k-subsets of X for any t |
