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%I #8 Mar 30 2012 18:37:27
%S 1,1,2,4,11,38,180,1182,10990,145271,2729980,72836122,2755533950,
%T 147695390782,11209247627416,1204126434867322,183035972377206269,
%U 39363771818346412010,11975532663667690562398,5153451004764204946993962
%N G.f.: A(x) = Sum_{n>=0} x^n / Product_{k=1..n} (1 - 2^(n-k)*x^k).
%F G.f. satisfies: A(2*x) = Sum_{n>=0} 2^n*x^n/Product_{k=1..n} (1-2^n*x^k).
%e G.f.: A(x) = 1 + x + 2*x^2 + 4*x^3 + 11*x^4 + 38*x^5 + 180*x^6 +...
%e where:
%e A(x) = 1 + x/(1-x) + x^2/((1-2*x)*(1-x^2)) + x^3/((1-4*x)*(1-2*x^2)*(1-x^3)) + x^4/((1-8*x)*(1-4*x^2)*(1-2*x^3)*(1-x^4)) + ...
%o (PARI) {a(n)=local(A=1);polcoeff(sum(m=0,n,x^m/prod(k=1,m,1-2^(m-k)*x^k +x*O(x^n))),n)}
%Y Cf. A193189, A193190, A193191.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Jul 17 2011
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