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%I #9 Nov 27 2019 02:45:18
%S 0,0,0,0,8,16,32,64,128,256,512,1024,768,1536,3072,6144,12288,24576,
%T 16384,32768,65536,131072,262144,524288,1048576,2097152,4194304,
%U 8388608,16777216,33554432,20971520,41943040,83886080,167772160
%N Number of subsets of {1, ..., n} containing exactly one twin prime pair.
%F a(n) = ceiling(A089881(n)/2)*2^(n-A089881(n)).
%Y Cf. A071538, A089827, A089828, A001359, A006512.
%K nonn
%O 1,5
%A _Reinhard Zumkeller_, Nov 13 2003