|
|
A066701
|
|
Triangle giving number of nonisomorphic minimal covering designs with parameters (n, k, k-1) (designs achieving the covering number C(n,k,k-1) given in A066010), for n >= 2, 2 <= k <= n.
|
|
1
|
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 5, 1, 6, 1, 1, 1, 1, 1, 77, 3, 2, 1, 1, 1, 1, 58, 1, 40, 1, 20, 1, 1, 1, 1, 2
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
2,18
|
|
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. This sequence says how many different solutions there are for C(n,k,k-1).
|
|
REFERENCES
|
CRC Handbook of Combinatorial Designs, 1996, p. 263.
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.
|
|
LINKS
|
|
|
CROSSREFS
|
Cf. A066010. A030129 gives entries in second column in the cases when a Steiner triple system exists.
A051390 gives entries in 3rd column in the cases when a Steiner quadruple system exists.
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|