OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n-1} (n-k+2)*A088716(k)*a(n-k-1) for n>0 with a(0)=1.
PROG
(PARI) {a(n)=local(A=Mat(1), B); for(m=2, n+3, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=1, B[i, j]=-j*(A^-1)[i-j, 1]); )); A=B); return((A^-1)[n+3, 3])}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 06 2005
STATUS
approved