A141892 Primes congruent to 10 mod 21.

31, 73, 157, 199, 241, 283, 367, 409, 577, 619, 661, 787, 829, 997, 1039, 1123, 1249, 1291, 1459, 1543, 1627, 1669, 1753, 1879, 2089, 2131, 2341, 2383, 2467, 2551, 2593, 2677, 2719, 2803, 2887, 2971, 3181, 3307, 3391, 3433, 3517, 3559, 3643, 3727, 3769, 3853

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, A124826.

Programs

Magma

[ p: p in PrimesUpTo(5000) | p mod 21 eq 10 ]; // Vincenzo Librandi, Apr 05 2011

Mathematica

Select[Range[10,5000,21],PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Apr 04 2011 *)
Select[Prime[Range[600]],Mod[#,21]==10&] (* Harvey P. Dale, Nov 20 2022 *)

PARI

is(n)=isprime(n) && n%21==10 \\ Charles R Greathouse IV, Jul 02 2016

Formula

a(n) ~ 12n log n. - Charles R Greathouse IV, Jul 02 2016