OFFSET
0,3
FORMULA
L.g.f.: exp(Sum_{n>=1} a(n)*x^n/n) = 1 + x*G(x) where G(x) = g.f. of A158109.
exp(Sum_{n>=1} a(n)*x^n/n) = [1 + Sum_{n>=1} C(2n-1,n)*a(n)*x^n]/[1 + Sum_{n>=1} (C(2n-1,n)-1)*a(n)*x^n].
EXAMPLE
L.g.f.: A(x) = x + 1*x^2/2 + 4*x^3/3 + 53*x^4/4 + 2321*x^5/5 +...
exp(A(x)) = 1 + x + 2*x^2 + 15*x^3 + 479*x^4 + 58981*x^5 +...
exp(A(x)) = 1 + x*G(x) where G(x) is the g.f. of A158109 such that:
log(G(x)) = x + 3*1*x^2/2 + 10*4*x^3/3 + 35*53*x^4/4 + 126*2321*x^5/5 +...
PROG
(PARI) {a(n)=local(A=x+x^2); if(n==0, 1, for(i=1, n-1, A=log(1+x*exp(sum(m=1, n, binomial(2*m-1, m)*x^m*polcoeff(A+x*O(x^m), m) )+x*O(x^n)))); n*polcoeff(A, n))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Mar 28 2009
STATUS
approved