%I #2 Mar 30 2012 18:37:07
%S 1,1,5,51,9163,1789359,2966784613,10246481110899,1164644624885859315,
%T 67519816893223600328475,31778915061906077887063371935,
%U 30252957250679839624103772879830589
%N a(n) = 2^[n(n+1) - A000120(n)] * [x^n] 1/(1-x)^(1/2^n) for n>=0, where A000120(n) = number of 1's in binary expansion of n.
%C [x^n] 1/(1-x)^(1/2^n) denotes the coefficient of x^n in the (2^n)-root of 1/(1-x).
%o (PARI) {a(n)=polcoeff(1/(1-x+x*O(x^n))^(1/2^n),n)*2^(n*(n+1)-subst(Pol(binary(n)),x,1))}
%Y Cf. A000120; A134098 (variant); A134096.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Oct 26 2007