A142198 Primes congruent to 39 mod 40.

79, 199, 239, 359, 439, 479, 599, 719, 839, 919, 1039, 1279, 1319, 1399, 1439, 1559, 1759, 1879, 1999, 2039, 2239, 2399, 2719, 2879, 2999, 3079, 3119, 3319, 3359, 3559, 3719, 3919, 4079, 4159, 4519, 4639, 4679, 4759, 4799, 4919, 4999, 5039, 5119, 5279, 5399

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.

Programs

Magma

[p: p in PrimesUpTo(7000) | p mod 40 eq 39 ]; // Vincenzo Librandi, Aug 22 2012

Mathematica

Select[Prime[Range[2000]],MemberQ[{39},Mod[#,40]]&] (* Vincenzo Librandi, Aug 22 2012 *)

PARI

is(n)=isprime(n) && n%40==39 \\ Charles R Greathouse IV, Jul 02 2016

Formula

a(n) ~ 16n log n. - Charles R Greathouse IV, Jul 02 2016