A023295 Primes that remain prime through 3 iterations of function f(x) = 8x + 9.

23, 643, 2293, 5023, 5653, 9643, 10723, 11503, 12823, 15493, 18353, 18773, 28403, 32003, 32183, 41953, 42853, 45233, 49853, 50873, 52103, 53113, 54623, 56123, 76003, 80803, 84443, 86783, 88813, 89413, 92033, 95213, 96823, 97943, 100613, 115793

Offset

1,1

Comments

Primes p such that 8*p+9, 64*p+81 and 512*p+657 are also primes. - Vincenzo Librandi, Aug 04 2010

Links

John Cerkan, Table of n, a(n) for n = 1..10000

a(n) == 3 (mod 10). - John Cerkan, Sep 24 2016

Mathematica

Select[Prime[Range[11000]], AllTrue[Rest[NestList[8#+9&, #, 3]], PrimeQ]&] (* Harvey P. Dale, Dec 30 2025 *)

Prog

(Magma) [n: n in [1..450000] | IsPrime(n) and IsPrime(8*n+9) and IsPrime(64*n+81) and IsPrime(512*n+657)]; // Vincenzo Librandi, Aug 04 2010

Crossrefs

Subsequence of A023232, A023264, and of A153762.

Sequence in context: A129991 A374304 A265681 * A169596 A142553 A123782

Adjacent sequences: A023292 A023293 A023294 * A023296 A023297 A023298

Keyword

nonn

Author

David W. Wilson

Status

approved