Wilson’s theorem for block designs
نویسنده
چکیده
Steiner systems S(2, k, v) For k ≥ 3, a Steiner system S(2, k, v) is usually defined as a pair (V,B), where V is a set of cardinality v of points and B is a set of k-element subsets of V , usually called blocks, or lines if the system has some geometric significance, with the property that each pair of points is contained in precisely one block. For example, to construct a Steiner system S(2, 3, 7) we may take V = {0, 1, 2, 3, 4, 5, 6} and
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