A089882 Number of subsets of {1, ..., n} containing exactly one twin prime pair.

0, 0, 0, 0, 8, 16, 32, 64, 128, 256, 512, 1024, 768, 1536, 3072, 6144, 12288, 24576, 16384, 32768, 65536, 131072, 262144, 524288, 1048576, 2097152, 4194304, 8388608, 16777216, 33554432, 20971520, 41943040, 83886080, 167772160

Offset

1,5

Links

Table of n, a(n) for n=1..34.

Formula

a(n) = ceiling(A089881(n)/2)*2^(n-A089881(n)).

Crossrefs

Cf. A071538, A089827, A089828, A001359, A006512.

Sequence in context: A256817 A281016 A048169 * A335850 A206375 A146541

Adjacent sequences: A089879 A089880 A089881 * A089883 A089884 A089885

Keyword

nonn

Author

Reinhard Zumkeller, Nov 13 2003

Status

approved