A023339 - OEIS

%I #24 Sep 08 2022 08:44:47

%S 9769,13781,17231,32059,32611,36251,46381,47417,55171,68927,103451,

%T 130447,182599,189671,220687,236627,241169,273641,275711,350219,

%U 374159,413951,471769,497579,498439,520631,521791,583777,601061,635809,647401

%N Primes that remain prime through 5 iterations of function f(x) = 4x + 3.

%C Primes p such that 4*p+3, 16*p+15, 64*p+63, 256*p+255 and 1024*p+1023 are also primes. - _Vincenzo Librandi_, Aug 05 2010

%H Paul Tek, <a href="/A023339/b023339.txt">Table of n, a(n) for n = 1..10000</a>

%t it5Q[n_]:=AllTrue[NestList[4#+3&,n,5],PrimeQ]; Select[Prime[ Range[ 60000]], it5Q] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Jul 05 2015 *)

%o (Magma) [n: n in [1..10000000] | IsPrime(n) and IsPrime(4*n+3) and IsPrime(16*n+15) and IsPrime(64*n+63) and IsPrime(256*n+255) and IsPrime(1024*n+1023)] // _Vincenzo Librandi_, Aug 05 2010

%K nonn

%O 1,1

%A _David W. Wilson_