OFFSET
0,4
COMMENTS
FORMULA
EXAMPLE
PROG
(PARI) {a(n)=if(n==0, 1, polcoeff(1-sum(k=0, n-1, a(k)*x^k*prod(j=1, k\2+1, 1-j*x+x*O(x^n))), n))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 21 2005
STATUS
approved