A142011 Primes congruent to 7 mod 31.

7, 131, 193, 317, 379, 503, 751, 937, 1061, 1123, 1433, 1619, 1867, 2053, 2239, 2549, 2797, 3169, 3541, 3727, 3851, 4099, 4409, 4657, 4967, 5153, 5711, 5897, 6269, 6703, 6827, 7013, 7757, 8191, 8377, 8501, 8563, 9059, 9431, 9679, 9803, 10733, 11353, 12097

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, A142005, A142006.

Programs

Magma

[ p: p in PrimesUpTo(30000) | p mod 31 eq 7 ]; // Vincenzo Librandi, Apr 20 2011

Mathematica

Select[Range[7,20000,31],PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Apr 20 2011 *)

PARI

is(n)=isprime(n) && n%31==7 \\ Charles R Greathouse IV, Jul 03 2016

Formula

a(n) ~ 30n log n. - Charles R Greathouse IV, Jul 03 2016