OFFSET
1,2
FORMULA
Product {k>=1} 1/(1 - x^k/(1 - x)) = exp(Sum_{k>=1} a(k)*x^k/k).
EXAMPLE
L.g.f.: L(x) = x/1 + 5*x^2/2 + 13*x^3/3 + 29*x^4/4 + 56*x^5/5 + 107*x^6/6 + 197*x^7/7 + 365*x^8/8 + ... .
exp(L(x)) = 1 + x + 3*x^2 + 7*x^3 + 16*x^4 + 35*x^5 + 76*x^6 + 162*x^7 + 342*x^8 + ... + A227682(n)*x^n + ... .
PROG
(PARI) N=66; x='x+O('x^N); Vec(x*deriv(log(1/prod(k=1, N, 1-x^k/(1-x)))))
(PARI) N=66; x='x+O('x^N); Vec(x*deriv(sum(k=1, N, x^k*sumdiv(k, d, 1/(d*(1-x)^d)))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 21 2019
STATUS
approved