A161220 The n-th member of a twin prime pair minus 2*n.

1, 1, 1, 3, 3, 5, 5, 13, 13, 21, 21, 35, 35, 43, 43, 69, 69, 71, 71, 97, 97, 105, 105, 131, 131, 139, 139, 141, 141, 167, 167, 175, 175, 201, 201, 209, 209, 235, 235, 267, 267, 335, 335, 343, 343, 369, 369, 425, 425, 469, 469, 495, 495, 509, 509, 529, 529, 543

Offset

1,4

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Formula

a(n)=A001097(n)-A005843(n).

Example

a(1) = 3-2*1=1. a(2) =5-2*2=1. a(3)=7-2*3=1. a(4)=11-2*4=3.

Mathematica

Module[{tp=Union[Flatten[Select[Partition[Prime[Range[150]], 2, 1], #[[2]]- #[[1]] == 2&]]]}, #[[1]]-#[[2]]&/@Thread[{tp, 2*Range[Length[tp]]}]] (* Harvey P. Dale, Feb 03 2022 *)

Crossrefs

Cf. A001097, A005843.

Sequence in context: A171710 A288983 A289768 * A032022 A335357 A325679

Adjacent sequences: A161217 A161218 A161219 * A161221 A161222 A161223

Keyword

nonn

Author

Juri-Stepan Gerasimov, Jun 06 2009

Extensions

Entries confirmed by R. J. Mathar, Jun 23 2009

Status

approved