OFFSET
0,2
EXAMPLE
G.f.: A(x) = 1 + 2*x + 4*x^2 + 9*x^3 + 14*x^4 + 29*x^5 + 44*x^6 + 77*x^7 + 120*x^8 + 195*x^9 + 291*x^10 + 453*x^11 + 673*x^12 + 998*x^13 + 1460*x^14 + 2101*x^15 + ...
PROG
(PARI) {a(n) = my(A = prod(k=1, n, sum(m=0, n, x^(k*m)/(1 - x^(m+k) +x*O(x^n)) )) ); polcoeff(A, n)}
for(n=0, 40, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Mar 15 2021
STATUS
approved