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G.f.: 1/(1-x) = Sum_{n>=0} a(n)*x^n/(1+x)^(2^(n+2)-4).
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%I #2 Mar 30 2012 18:37:21

%S 1,1,5,51,1059,44620,3795202,649054326,222639357434,152968659433948,

%T 210361428050679489,578800452225641673965,3185715127946958245708501,

%U 35071788327149162320178667272,772254422082165524711277630023576

%N G.f.: 1/(1-x) = Sum_{n>=0} a(n)*x^n/(1+x)^(2^(n+2)-4).

%F Column 2 of triangle A172400.

%e 1/(1-x) = 1 + x/(1+x)^4 + 5*x^2/(1+x)^12 + 51*x^3/(1+x)^28 + 1059*x^4/(1+x)^60 +...

%o (PARI) {a(n)=if(n==0,1,polcoeff(-(1-x)*sum(m=0,n-1,a(m)*x^m/(1+x +x*O(x^n))^(2^(m+2)-4)),n))}

%Y Cf. A172400, A172401, A172402.

%K nonn

%O 0,3

%A _Paul D. Hanna_, Feb 01 2010