Generating successive incomplete blocks with each pair of elements in at least one block
نویسندگان
چکیده
منابع مشابه
On the non-existence of pair covering designs with at least as many points as blocks
We establish new lower bounds on the pair covering number Cλ(v, k) for infinitely many values of v, k and λ, including infinitely many values of v and k for λ = 1. Here, Cλ(v, k) denotes the minimum number of k-subsets of a v-set of points such that each pair of points occurs in at least λ of the k-subsets. We use these results to prove simple numerical conditions which are both necessary and s...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 1972
ISSN: 0097-3165
DOI: 10.1016/0097-3165(72)90085-4