%I #4 Mar 30 2012 18:37:26
%S 1,1,2,19,253,5256,153121,5793349,292530822,18658710139,1476004466687,
%T 143228682526672,16603062548806759,2272210780577578355,
%U 363396388117576899042,67028665570181029621005,14142153576677394736652147
%N G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(n^4).
%e G.f.: A(x) = 1 + x + 2*x^2 + 19*x^3 + 253*x^4 + 5256*x^5 + 153121*x^6 +...
%e where the g.f. satisfies:
%e A(x) = 1 + x*A(x) + x^2*A(x)^16 + x^3*A(x)^81 + x^4*A(x)^256 + x^5*A(x)^625 + x^6*A(x)^1296 +...+ x^n*A(x)^(n^4) +...
%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^4)));polcoeff(A,n)}
%Y Cf. A107595, A191805, A191807, A191808.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Jun 16 2011