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%I #10 Dec 26 2023 09:41:56
%S 1,1,3,8,23,67,202,622,1955,6248,20261,66484,220429,737260,2484734,
%T 8429714,28766001,98670291,340011308,1176505537,4086143638,
%U 14239716570,49776772808,174492148048,613266137776,2160518118345,7628244051977,26988540797766,95666557041459
%N G.f. satisfies: A(x) = exp( Sum_{n>=1} (1+x)^n * A(x^n) * x^n/n ).
%e G.f.: A(x) = 1 + x + 3*x^2 + 8*x^3 + 23*x^4 + 67*x^5 + 202*x^6 + 622*x^7 +...
%e where
%e log(A(x)) = (1+x)*A(x)*x + (1+x)^2*A(x^2)*x^2/2 + (1+x)^3*A(x^3)*x^3/3 +...
%o (PARI) {a(n)=local(A=1+x);for(i=1,n,A=exp(sum(m=1,n,(1+x)^m*x^m/m*subst(A,x,x^m+x*O(x^n)))));polcoeff(A,n)}
%Y Cf. A199104.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Nov 03 2011
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