A141963 Primes congruent to 23 mod 27.

23, 131, 239, 293, 347, 401, 509, 563, 617, 887, 941, 1049, 1103, 1319, 1373, 1427, 1481, 1697, 1913, 2129, 2237, 2399, 2777, 2939, 3209, 3371, 3533, 3803, 3911, 4019, 4073, 4127, 4289, 4397, 4451, 4721, 4937, 5099, 5153, 5261, 5477, 5531, 5639, 5693, 5801

Offset: 1

Author

N. J. A. Sloane, Jul 11 2008

Keywords

• nonn
• easy

Links

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

Crossrefs

Cf. A000040, A141964, A141965.

Programs

Magma

[p: p in PrimesUpTo(7000) | p mod 27 eq 23 ]; // Vincenzo Librandi, Aug 16 2012

Mathematica

Select[Range[23, 30000, 27], PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Jun 21 2011 *)

PARI

is(n)=isprime(n) && n%27==23 \\ Charles R Greathouse IV, Jul 02 2016

Formula

a(n) ~ 18n log n. - Charles R Greathouse IV, Jul 02 2016