|
| |
|
|
A005786
|
|
Number of 6-covers of an n-set.
(Formerly M4244)
|
|
8
|
|
|
|
6, 43, 336, 2864, 25326, 223034, 1890123, 15115098, 112980937, 787320629, 5121184083, 31188412225, 178517111561, 964196387369, 4933278065881, 23997707450765, 111358094980387, 494444748602595, 2106504840061571
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
REFERENCES
|
R. J. Clarke, Covering a set by subsets, Discrete Math., 81 (1990), 147-152.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
|
LINKS
|
Table of n, a(n) for n=1..19.
Vladeta Jovovic, Binary matrices up to row and column permutations
|
|
|
CROSSREFS
|
Cf. A005785.
Sequence in context: A025594 A098665 A153397 * A071541 A146966 A240653
Adjacent sequences: A005783 A005784 A005785 * A005787 A005788 A005789
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
N. J. A. Sloane.
|
|
|
EXTENSIONS
|
More terms from Vladeta Jovovic, Jun 12 2000
|
|
|
STATUS
|
approved
|
| |
|
|
