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a(n) = [x^n] G(x)^(2^(n+1)) where G(x) satisfies: [x^(n+1)] G(x)^(2^n) = [x^n] G(x)^(2^n) for n>=0 and G(2x) is the g.f. of A134084.
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%I #3 Mar 30 2012 18:37:07

%S 1,4,32,672,42816,8822400,6065609984,14256471226880,

%T 117000916309144576,3410202131850138806272,

%U 357670541003601468527333376,136391046228660672398602237353984

%N a(n) = [x^n] G(x)^(2^(n+1)) where G(x) satisfies: [x^(n+1)] G(x)^(2^n) = [x^n] G(x)^(2^n) for n>=0 and G(2x) is the g.f. of A134084.

%F a(n) = 2^n * A134089(n).

%o (PARI) {a(n)=local(A=[1],B);for(i=1,n,A=concat(A,0); B=Vec(Ser(A)^(2^(#A-2)));A[ #A]=(B[ #B-1]-B[ #B])/2^(#A-2));Vec(Ser(A)^(2^(n+1)))[n+1]}

%Y Cf. A134084, A134085, A134086, A134088, A134089.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Oct 26 2007