A142606 Primes congruent to 7 mod 55.

7, 227, 337, 557, 887, 997, 1217, 1327, 1657, 1877, 1987, 2207, 2647, 3307, 3527, 3637, 3967, 4297, 4517, 4957, 5507, 6277, 6607, 6827, 7487, 7817, 7927, 8147, 8807, 9137, 9467, 9907, 10457, 10567, 11117, 11447, 11777, 11887, 12107, 12437, 12547, 13537

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Formula

a(n) ~ 40n log n. - Charles R Greathouse IV, Jul 04 2016

Mathematica

Select[Prime[Range[2500]], MemberQ[{7}, Mod[#, 55]] &] (* Vincenzo Librandi, Aug 31 2012 *)
Select[Range[7, 14000, 55], PrimeQ] (* Harvey P. Dale, Dec 31 2013 *)

Prog

(Magma) [p: p in PrimesUpTo(16000) | p mod 55 eq 7]; // Vincenzo Librandi, Aug 31 2012
(PARI) is(n)=isprime(n) && n%55==7 \\ Charles R Greathouse IV, Jul 04 2016

Crossrefs

Cf. A000040.

Sequence in context: A193503 A303533 A372967 * A123832 A093167 A157693

Adjacent sequences: A142603 A142604 A142605 * A142607 A142608 A142609

Keyword

nonn,easy

Author

N. J. A. Sloane, Jul 11 2008

Status

approved