A217918 Positions of 2 in sequence A217916.

1, 4, 11, 29, 46, 121, 172, 191, 254, 1276, 1432, 1654, 2416, 2486, 5254, 9181, 9592, 10012, 10441, 11629, 12881, 14029, 14197, 16472, 20707, 22367, 23872, 24532, 24977, 26336, 26797, 27496, 28681, 29162, 37951, 38227, 40756

Offset

1,2

Links

Table of n, a(n) for n=1..37.

Formula

Involves triangular-indexed twin primes:

prime(a(n)) - prime(a(n)-1) = 2 for n>1 with a(1)=1.

Crossrefs

Cf. A217916, A217919.

Sequence in context: A113067 A290890 A152689 * A360447 A000604 A153876

Adjacent sequences: A217915 A217916 A217917 * A217919 A217920 A217921

Keyword

nonn

Author

Paul D. Hanna, Mar 04 2013

Status

approved