A023303 Primes that remain prime through 4 iterations of function f(x) = 2x + 3.

47, 67, 97, 137, 307, 1427, 2857, 6047, 6997, 9377, 12097, 16057, 24197, 32117, 35117, 36877, 44507, 46687, 54517, 55487, 64877, 71327, 71807, 76537, 89017, 92387, 94427, 100057, 132707, 142057, 153077, 160207, 184777, 186647, 194027, 200117, 205237

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Comments

Primes p such that 2*p+3, 4*p+9, 8*p+21 and 16*p+45 are also primes. - Vincenzo Librandi, Aug 04 2010

Links

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

Crossrefs

Subsequence of A023204.

Programs

Magma

[ p: p in PrimesUpTo(300000) | IsPrime(p) and IsPrime(2*p+3) and IsPrime(4*p+9) and IsPrime(8*p+21) and IsPrime(16*p+45)] // Vincenzo Librandi, Aug 04 2010

Mathematica

Select[Prime[Range[20000]],And@@PrimeQ[NestList[2#+3&,#,4]]&] (* Harvey P. Dale, Aug 12 2012 *)