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%I #2 Mar 30 2012 18:37:17
%S 1,1,1,4,11,42,196,988,5314,30724,189962,1244264,8583042,62112639,
%T 469917193,3707053139,30421506639,259182853643,2288352779166,
%U 20904648990227,197305045507448,1921509079008868,19285642292478101
%N G.f. A(x) equals the composition of functions x*(1 + a(n)*x^n); let F_1(x) = x, F_{n+1}(x) = x*(1 + a(n)*F_n(x)^n), then A(x) = limit F_n(x): A(x) = ...o x*(1+a(n)*x^n) o...o x*(1+a(2)*x^2) o x*(1+a(1)*x).
%e G.f.: A(x) = x + x^2 + x^3 + 4*x^4 + 11*x^5 + 42*x^6 + 196*x^7 +...
%e A(x) = ...o x*(1+11*x^5) o x*(1+4*x^4) o x*(1+x^3) o x*(1+x^2) o x*(1+x).
%o (PARI) {a(n)=local(F=x); if(n<1, 0, for(k=2, n, F=subst(x+a(k-1)*x^k +x*O(x^n),x,F); ); return(polcoeff(F, n)))}
%Y Cf. A119472 (variant).
%K nonn
%O 1,4
%A _Paul D. Hanna_, Aug 10 2009
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