A089144 Primes p such that 6*p-5 and 6*p-1 are primes.

2, 3, 7, 17, 19, 47, 53, 59, 67, 103, 113, 127, 157, 239, 269, 283, 313, 379, 383, 397, 449, 467, 577, 613, 617, 647, 823, 829, 907, 929, 977, 1097, 1123, 1279, 1373, 1447, 1489, 1523, 1697, 1723, 1789, 1877, 1933, 2017, 2027, 2063, 2069, 2237, 2339, 2423

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..4000

Example

6*7=42, 42-5=37, 42-1=41, 37 and 41 primes.

Mathematica

okQ[n_]:=Module[{x=6n}, PrimeQ[x-1]&&PrimeQ[x-5]]; Select[Prime[Range[ 500]], okQ] (* Harvey P. Dale, May 25 2011 *)
Select[Prime[Range[400]], PrimeQ[6 # - 5] && PrimeQ[6 # - 1]&] (* Vincenzo Librandi, May 23 2017 *)

Prog

(Magma) [p: p in PrimesUpTo(3000) |IsPrime(6*p-5) and IsPrime(6*p-1)]; // Vincenzo Librandi, May 23 2017

Crossrefs

Cf. A090606, A090607, A090608, A090609, A090610.

Sequence in context: A154431 A350118 A256917 * A171430 A355419 A045332

Adjacent sequences: A089141 A089142 A089143 * A089145 A089146 A089147

Keyword

easy,nonn

Author

Pierre CAMI, Dec 05 2003

Extensions

More terms from Ray Chandler, Dec 06 2003

Status

approved