ABSTRACT
S ∈ Pt−1(Nn)}, where Pt−1(Nn) is the set of all subsets of Nn of size (t − 1). Then (X,B) is a tBD that is not s-balanced for any 0 < s < t.
63.13 Remark Under certain conditions a tBD does possess balance for other values of 0 < s < t (see [1244]).
