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%I #2 Mar 30 2012 18:37:16
%S 1,1,2,5,20,182,6552,1517473,4654013540,520378069012098,
%T 10766981089503125653501,448728931430680787386854758969563,
%U 1010943666488949958707946804366787268947495194377
%N G.f.: A(x) = exp(Sum_{n>=1} A158873(n)*x^n/n) = exp(Sum_{n>=1} (1 + A158873(n)*x)^n*x^n/n).
%e G.f.: A(x) = 1 + x + 2*x^2 + 5*x^3 + 20*x^4 + 182*x^5 + 6552*x^6 +...
%e Let L(x) = g.f. of A158873 where exp(L(x)) = A(x), then:
%e L(x) = x + 3*x^2/2 + 10*x^3/3 + 59*x^4/4 + 796*x^5/5 + 38106*x^6/6 +...
%e L(x) = (1+x)*x + (1+3*x)^2*x^2/2 + (1+10*x)^3*x^3/3 + (1+59*x)^4*x^4/4 +...
%o (PARI) {a(n)=local(A=1+x);if(n==0,1,for(i=0,n,A=exp(sum(m=1,n,(1+m*polcoeff(log(A+x*O(x^m)),m)*x+x*O(x^n))^m*x^m/m)));polcoeff(A,n))}
%Y Cf. A158873 (log).
%K nonn
%O 0,3
%A _Paul D. Hanna_, Apr 10 2009
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