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A066011 Covering numbers C(n,8,7). 2
1, 8, 20, 63, 126 (list; graph; refs; listen; history; internal format)
OFFSET

8,2

COMMENTS

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.

REFERENCES

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.

LINKS

D. Applegate, E. M. Rains and N. J. A. Sloane, On asymmetric coverings and covering numbers, J. Comb. Des. 11 (2003), 218-228.

D. Gordon, La Jolla Repository of Coverings

K. J. Nurmela and P. R. J. Ostergard, New coverings of t-sets with (t+1)-sets, J. Combinat. Designs, 7 (1999), 217-226.

K. J. Nurmela and P. R. J. Ostergard, New coverings of t-sets with (t+1)-sets (appendix), J. Combinat. Designs, 7 (1999), 217-226.

Index entries for covering numbers

CROSSREFS

A column of A066010.

Sequence in context: A179756 A101363 A003685 * A007016 A129550 A014584

Adjacent sequences:  A066008 A066009 A066010 * A066012 A066013 A066014

KEYWORD

nonn,hard

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 15 21:07 EST 2012. Contains 205856 sequences.