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G.f. A(x) satisfies: A(x) = 1 + Sum_{n>=1} x^n*A(x)^(n!).
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%I #7 Mar 30 2012 18:37:26

%S 1,1,2,5,17,83,686,12702,618670,86594397,34022042977,39695020615741,

%T 145648823360677102,1642319452761786618544,65668928064214050537574257,

%U 8555753375062844432074207650070,4182704217109744221309611775526547951

%N G.f. A(x) satisfies: A(x) = 1 + Sum_{n>=1} x^n*A(x)^(n!).

%e G.f.: A(x) = 1 + x + 2*x^2 + 5*x^3 + 17*x^4 + 83*x^5 + 686*x^6 +...

%e The g.f. satisfies:

%e A(x) = 1 + x*A(x) + x^2*A(x)^2 + x^3*A(x)^6 + x^4*A(x)^24 + x^5*A(x)^120 + x^6*A(x)^720 + x^7*A(x)^5040 +...+ x^n*A(x)^(n!) +...

%o (PARI) {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(m!)));polcoeff(A,n)}

%K nonn

%O 0,3

%A _Paul D. Hanna_, Jun 19 2011