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%I #11 Jun 21 2013 22:46:57
%S 1,1,4,9,26,64,183,465,1282,3406,9285,25044,68511,186565,511559,
%T 1402689,3858355,10623592,29311035,80957054,223924131,619998655,
%U 1718508780,4767643956,13238487101,36788341279,102306350929,284699560049,792766449887,2208805757329,6157550533161
%N L.g.f. L(x) = Sum_{n>=1} a(n)*x^n/n satisfies: exp(L(x)) = 1 + x*exp( Sum_{n>=1} a(n)*exp(L(x^n))*x^n/n ).
%F Logarithmic derivative of A226907.
%e G.f.: L(x) = x + x^2/2 + 4*x^3/3 + 9*x^4/4 + 26*x^5/5 + 64*x^6/6 +...
%e where G(x) = exp(L(x)) satisfies
%e G(x) = 1 + x*exp( x*G(x) + x^2*G(x^2)/2 + 4*x^3*G(x^3)/3 + 9*x^4*G(x^4)/4 + 26*x^5*G(x^5)/5 + 64*x^6*G(x^6)/6 +...+ a(n)*x^n*G(x^n)/n +... )
%e and equals the g.f. of A226907:
%e G(x) = 1 + x + x^2 + 2*x^3 + 4*x^4 + 9*x^5 + 20*x^6 + 48*x^7 + 113*x^8 + 276*x^9 + 677*x^10 +...+ A226907(n)*x^n +...
%o (PARI) {a(n)=local(A=1+x);for(i=1,n,A=1+x*exp(sum(m=1,n,polcoeff(log(A+x*O(x^m)),m)*subst(A,x,x^m)*x^m)+x*O(x^n)));n*polcoeff(log(A),n)}
%o for(n=1,25,print1(a(n),", "))
%Y Cf. A226907.
%K nonn
%O 1,3
%A _Paul D. Hanna_, Jun 21 2013
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