A023292 Primes that remain prime through 3 iterations of function f(x) = 8x + 3.

31, 191, 821, 3271, 11171, 13121, 14591, 21521, 27751, 30341, 35951, 37561, 39671, 40231, 43651, 51061, 51551, 56671, 68161, 73681, 84871, 91541, 92581, 102031, 102871, 102881, 104971, 117281, 127781, 128201, 128551, 128761, 138511, 148091

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Comments

Primes p such that 8*p+3, 64*p+27 and 512*p+219 are also primes. - Vincenzo Librandi, Aug 04 2010

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Programs

Magma

[n: n in [1..450000] | IsPrime(n) and IsPrime(8*n+3) and IsPrime(64*n+27) and IsPrime(512*n+219)]; // Vincenzo Librandi, Aug 04 2010

Mathematica

Select[Prime[Range[14000]],AllTrue[Rest[NestList[8#+3&,#,3]],PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 09 2015 *)