OFFSET
0,3
COMMENTS
The recurrence for A000311, with slightly different initial conditions.
LINKS
T. D. Noe, Table of n, a(n) for n = 0..100
MAPLE
M:=50; a:=array(0..100); a[0]:=0; a[1]:=1; lprint(0, a[0]); lprint(1, a[1]); for n from 1 to M do a[n+1]:=(n+2)*a[n]+2*add(binomial(n, k)*a[k]*a[n-k+1], k=2..n-1); lprint(n+1, a[n+1]); od:
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 30 2006
STATUS
approved