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%I #3 Mar 30 2012 18:50:42
%S 1,2,4,12,24,48,96,192,448,896,1792,3584,7168,14336,28672,61440,
%T 122880,245760,491520,983040,1966080,3932160,7864320,15728640,
%U 32505856,65011712,130023424,260046848,520093696,1040187392
%N Number of subsets of {1,.., n} containing at least one square.
%C a(n) = Sum(A089886(n,k): 1<=k<=A000196(n)) = A000079(n)-A089887(n) = A089887(n)*A000225(A000196(n)).
%F a(n) = (2^(n^(1/2))-n^(1/2))*2^(n-1).
%Y Cf. A089890.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Nov 13 2003
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