A127487 Primes p such that 6p - 31 and 6p + 31 are also primes.

2, 7, 13, 47, 113, 163, 167, 197, 233, 307, 317, 373, 547, 617, 797, 827, 863, 937, 1087, 1213, 1223, 1367, 1483, 1567, 1597, 1783, 1787, 2003, 2063, 2087, 2137, 2203, 2333, 2393, 2437, 2543, 2617, 2693, 2777, 2903, 3037, 3067, 3163, 3347, 3463, 3583, 3607

Offset

1,1

Links

Table of n, a(n) for n=1..47.

Example

7, 6*7 - 31 = 11, and 6*7 + 31 = 73 are all primes.

Mathematica

Select[Range[8000], PrimeQ[ # ] && PrimeQ[6# + 31] && PrimeQ[6# - 31] &]
Select[Prime[Range[600]], And@@PrimeQ[6#+{31, -31}]&] (* Harvey P. Dale, Mar 28 2012 *)

Prog

(Magma) [ p: p in PrimesUpTo(9000) | IsPrime(6*p-31) and IsPrime(6*p+31)] // Vincenzo Librandi, Jan 29 2011

Crossrefs

Sequence in context: A153136 A178607 A321407 * A226140 A180003 A211874

Adjacent sequences: A127484 A127485 A127486 * A127488 A127489 A127490

Keyword

nonn

Author

Zerinvary Lajos, Mar 31 2007

Status

approved