|
| |
|
|
A052890
|
|
A simple grammar.
|
|
0
| |
|
|
1, 1, 2, 6, 16, 49, 153, 493, 1623, 5460, 18625, 64373, 224843, 792546, 2815443, 10070115, 36233440, 131063713, 476320360, 1738401482, 6368750019
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,3
|
|
|
LINKS
| INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 866
|
|
|
MAPLE
| spec := [S, {B=Set(C, 1 <= card), C=Prod(Z, S), S=PowerSet(B)}, unlabeled]: seq(combstruct[count](spec, size=n), n=0..20);
|
|
|
CROSSREFS
| Sequence in context: A151528 A132803 A079565 * A052814 A192401 A151445
Adjacent sequences: A052887 A052888 A052889 * A052891 A052892 A052893
|
|
|
KEYWORD
| easy,nonn
|
|
|
AUTHOR
| encyclopedia(AT)pommard.inria.fr, Jan 25 2000
|
| |
|
|
