A137877 Numbers k such that 18*k - 1 and 18*k + 1 are twin primes.

1, 4, 6, 10, 11, 15, 24, 29, 45, 46, 49, 59, 64, 71, 90, 104, 111, 116, 119, 126, 130, 144, 155, 165, 176, 181, 185, 196, 199, 204, 214, 225, 231, 235, 241, 249, 251, 266, 274, 276, 279, 301, 314, 319, 325, 326, 350, 364, 365, 370, 386, 396, 406, 416, 420, 431

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

1 is in the sequence since 18*1 - 1 = 17 and 18*1 + 1 = 19 are twin primes.

Mathematica

q=18; lst={}; Do[r=n*q; If[PrimeQ[r-1]&&PrimeQ[r+1], AppendTo[lst, n]], {n, 1, 10^3}]; lst (* Vladimir Joseph Stephan Orlovsky, Aug 07 2008 *)

Crossrefs

Cf. A124519, A135023, A135368, A137876.

Sequence in context: A109270 A187331 A184923 * A246022 A174240 A328321

Adjacent sequences: A137874 A137875 A137876 * A137878 A137879 A137880

Keyword

nonn

Author

Zak Seidov, Feb 19 2008

Status

approved