|
Search: id:A052596
|
|
|
| A052596 |
|
A simple regular expression in a labeled universe. |
|
+0
1
|
|
| 1, 1, 2, 6, 48, 120, 720, 5040, 40320, 362880, 3628800, 39916800, 479001600, 6227020800, 87178291200, 1307674368000, 20922789888000, 355687428096000, 6402373705728000, 121645100408832000, 2432902008176640000
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
LINKS
|
INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 541
|
|
FORMULA
|
E.g.f.: (-1-x^4+x^5)/(-1+x)
Recurrence: {a(1)=1, a(0)=1, (-1-n)*a(n)+a(n+1), a(3)=6, a(2)=2, a(5)=120, a(4)=48}
n!
|
|
MAPLE
|
spec := [S, {S=Union(Sequence(Z), Prod(Z, Z, Z, Z))}, labeled]: seq(combstruct[count](spec, size=n), n=0..20);
|
|
CROSSREFS
|
Sequence in context: A078537 A145502 A072444 this_sequence A098710 A052614 A052688
Adjacent sequences: A052593 A052594 A052595 this_sequence A052597 A052598 A052599
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
encyclopedia(AT)pommard.inria.fr, Jan 25 2000
|
|
|
Search completed in 0.002 seconds
|
