OFFSET
0,2
LINKS
John Riordan, Letter, Apr 28 1976.
FORMULA
O.g.f.: Sum_{n>=0} x^n / Product_{k=1..n+1} (1-k^3*x). [From Paul D. Hanna, Feb 15 2012]
G.f.: (1 - G(0) )/(1-x) where G(k) =1 - 1/(1 - x*k^3)/(1-x/(x-1/G(k+1) )); (recursively defined continued fraction). - Sergei N. Gladkovskii, Jan 17 2013
PROG
(PARI) {a(n)=polcoeff(sum(m=0, n, x^m/prod(k=1, m+1, 1-k^3*x +x*O(x^n))), n)} /* Paul D. Hanna, Feb 15 2012 */
CROSSREFS
KEYWORD
nonn
AUTHOR
Ralf Stephan, Sep 08 2004
STATUS
approved