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A066040
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Triangle of covering numbers T(n,k) = C(n,k,k-3), n >= 4, 4 <= k <= n.
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0
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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, 16, 10, 8, 1
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OFFSET
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4,2
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COMMENTS
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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.
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REFERENCES
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CRC Handbook of Combinatorial Designs, 1996, p. 263.
W. H. Mills and R. C. Mullin, Coverings and packings, pp. 371-399 of J. H. Dinitz and D. R. Stinson, editors,a Contemporary Design Theory, Wiley, 1992.
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LINKS
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Table of n, a(n) for n=4..39.
D. Gordon, La Jolla Repository of Coverings
Index entries for covering numbers
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EXAMPLE
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1; 2 1; 2 3 1; 2 3 4 1; 2 4 4 5 1; ...
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CROSSREFS
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Sequence in context: A195097 A181845 A183534 * A066019 A051237 A064379
Adjacent sequences: A066037 A066038 A066039 * A066041 A066042 A066043
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KEYWORD
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nonn,tabl,more
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AUTHOR
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N. J. A. Sloane, Dec 30 2001
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STATUS
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approved
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