%I #10 Feb 02 2020 21:28:42
%S 1,2,1,2,3,1,2,3,4,1,2,4,4,5,1,3,5,7,6,6,1,3,6,10,10,8,7,1,3,7,11,17,
%T 16,10,8,1
%N Triangle of covering numbers T(n,k) = C(n,k,k-3), n >= 4, 4 <= k <= n.
%C C(v,k,t) is the smallest number of k-subsets of an n-set such that every t-subset is contained in at least one of the k-subsets.
%D CRC Handbook of Combinatorial Designs, 1996, p. 263.
%D W. H. Mills and R. C. Mullin, Coverings and packings, pp. 371-399 of Jeffrey H. Dinitz and D. R. Stinson, editors, Contemporary Design Theory, Wiley, 1992.
%H D. Gordon, <a href="http://www.dmgordon.org/cover">La Jolla Repository of Coverings</a>
%H <a href="/index/Cor#covnum">Index entries for covering numbers</a>
%e 1; 2 1; 2 3 1; 2 3 4 1; 2 4 4 5 1; ...
%K nonn,tabl,more
%O 4,2
%A _N. J. A. Sloane_, Dec 30 2001