A142371 - OEIS

%I #11 Sep 08 2022 08:45:36

%S 67,349,443,631,1289,1571,1759,2417,2699,2887,3169,3733,4297,4391,

%T 4673,4861,5237,5519,5801,6271,6553,7211,7681,7963,8527,9091,9467,

%U 9749,10313,10501,11159,12569,12757,13697,14449,14543,14731,15013,15107,15671,15859

%N Primes congruent to 20 mod 47.

%H Vincenzo Librandi, <a href="/A142371/b142371.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) ~ 46n log n. - _Charles R Greathouse IV_, Jul 03 2016

%t Select[Prime[Range[2500]],MemberQ[{20},Mod[#,47]]&] (* _Vincenzo Librandi_, Aug 27 2012 *)

%t Select[Range[20,16000,47],PrimeQ] (* _Harvey P. Dale_, Jun 01 2018 *)

%o (Magma) [p: p in PrimesUpTo(18000) | p mod 47 eq 20]; // _Vincenzo Librandi_, Aug 27 2012

%o (PARI) is(n)=isprime(n) && n%47==20 \\ _Charles R Greathouse IV_, Jul 03 2016

%Y Cf. A000040.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_, Jul 11 2008