A023268 Primes that remain prime through 2 iterations of function f(x) = 9x + 10.

11, 13, 43, 47, 67, 83, 89, 103, 109, 193, 197, 251, 281, 293, 383, 397, 449, 461, 601, 617, 641, 733, 757, 823, 839, 853, 887, 937, 967, 1013, 1069, 1091, 1447, 1489, 1733, 1741, 1789, 1931, 2111, 2237, 2239, 2251, 2339, 2521, 2539, 2647, 2671, 2693, 2797

Offset

1,1

Comments

Primes p such that 9*p+10 and 81*p+100 are also primes. - Vincenzo Librandi, Aug 04 2010

Links

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

Mathematica

Select[Prime[Range[500]], And@@PrimeQ[Rest[NestList[9#+10&, #, 2]]]&] (* Harvey P. Dale, Jul 13 2012 *)

Prog

(Magma) [n: n in [1..100000] | IsPrime(n) and IsPrime(9*n+10) and IsPrime(81*n+100)] // Vincenzo Librandi, Aug 04 2010

Crossrefs

Sequence in context: A329175 A045467 A108264 * A154292 A188386 A027450

Adjacent sequences: A023265 A023266 A023267 * A023269 A023270 A023271

Keyword

nonn

Author

David W. Wilson

Status

approved