A059323 Smaller term of closest safe prime pairs.

11, 47, 167, 347, 467, 1307, 2027, 2447, 4127, 4787, 5087, 5387, 5927, 12527, 12647, 15287, 18947, 28307, 39107, 39827, 41507, 44687, 51827, 63587, 64007, 71987, 73847, 76367, 76907, 78467, 79967, 83207, 118787, 121547, 143687, 164987

Offset

1,1

Links

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

Formula

{x| both x and x+12 are safe primes}; Intersection(12+A005385, primes)

Example

11 and 23 are consecutive safe primes but not consecutive primes; 467 and 479 are consecutive safe primes and consecutive primes as well. Both 11 and 467 are here.

Mathematica

seqQ[n_] := And @@ PrimeQ[{n, n+12, (n-1)/2, (n+11)/2}]; Select[Range[165000], seqQ] (* Amiram Eldar, Jan 13 2020 *)

Prog

(Magma) [p:p in PrimesUpTo(165000)| IsPrime(p+12) and IsPrime((p-1) div 2) and IsPrime( (p+11) div 2)]; // Marius A. Burtea, Jan 13 2020

Crossrefs

Cf. A005383, A033299.

Sequence in context: A036489 A076306 A219079 * A267614 A123984 A141282

Adjacent sequences: A059320 A059321 A059322 * A059324 A059325 A059326

Keyword

nonn

Author

Labos Elemer, Jan 26 2001

Extensions

Offset corrected by Amiram Eldar, Jan 13 2020

Status

approved