|
Search: id:A110609
|
|
| |
|
| 0, 1, 8, 45, 224, 1050, 4752, 21021, 91520, 393822, 1679600, 7113106, 29953728, 125550100, 524190240, 2181340125, 9051563520, 37467344310, 154754938800, 637982011590, 2625648168000, 10789623755820, 44277560801760
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
COMMENT
|
Second column of number triangle A110608.
|
|
FORMULA
|
a(n)=n^2*binomial(2n, n)/(n+1)=n^2*A000108(n)=A002736(n)/(n+1).
|
|
MAPLE
|
with(combinat):with(combstruct):a[0]:=0:for n from 1 to 30 do a[n]:=sum((count(Composition(n*2+1), size=n)), j=1..n) od: seq(a[n], n=0..22); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 09 2007
a:=n->sum(sum(binomial(2*n, n)/(n+1), j=1..n), k=1..n): seq(a(n), n=0..22); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 09 2007
|
|
MATHEMATICA
|
Table[CatalanNumber[n]*n^2, {n, 0, 22}] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jul 08 2009]
|
|
CROSSREFS
|
Sequence in context: A002696 A016208 A026852 this_sequence A032208 A163003 A055422
Adjacent sequences: A110606 A110607 A110608 this_sequence A110610 A110611 A110612
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), Jul 30 2005
|
|
|
Search completed in 0.002 seconds
|
