OFFSET
0,3
EXAMPLE
G.f.: A(x) = 1 + x + 2*x^2 + 5*x^3 + 14*x^4 + 40*x^5 + 154*x^6 +...
log(A(x)) = (1+x)*x + (1+3*x)^2*x^2/2 + (1+4*x)^3*x^3/3 + (1+7*x)^4*x^4/4 +...
log(A(x)) = x + 3*x^2/2 + 10*x^3/3 + 35*x^4/4 + 116*x^5/5 + 606*x^6/6 +... (A159309)
PROG
(PARI) {a(n)=polcoeff(exp(sum(m=1, n+1, (1+sigma(m)*x+x*O(x^n))^m*x^m/m)), n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Apr 10 2009
STATUS
approved