%I #3 Apr 21 2012 17:40:44
%S 1,1,2,8,48,382,3756,43756,587624,8924812,151144684,2823121164,
%T 57649783664,1277765175416,30551583576144,783907809051392,
%U 21486223682939760,626575942278440112,19371271089840844552,632894233658705820660,21789691181582852824488
%N G.f. satisfies: A(x) = x + x^2 * A'(A(x)).
%e G.f.: A(x) = x + x^2 + 2*x^3 + 8*x^4 + 48*x^5 + 382*x^6 + 3756*x^7 +...
%e Related expansions:
%e A'(x) = 1 + 2*x + 6*x^2 + 32*x^3 + 240*x^4 + 2292*x^5 + 26292*x^6 +...
%e A(A(x)) = x + 2*x^2 + 6*x^3 + 27*x^4 + 166*x^5 + 1306*x^6 + 12556*x^7 +...
%o (PARI) {a(n)=local(A=x+x^2+x*O(x^n));for(i=1,n,A=x+x^2*subst(A',x,A));polcoeff(A,n)}
%o for(n=1,21,print1(a(n),", "))
%Y Cf. A211828.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Apr 21 2012
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