A023337 Primes that remain prime through 5 iterations of function f(x) = 3x + 8.

3181, 61981, 134291, 342821, 459091, 882451, 984931, 1016011, 1028471, 1181701, 1391561, 1897801, 2009311, 2272301, 2476421, 2769791, 3048041, 3085421, 3128821, 3207221, 3545111, 4092931, 4690591, 5015321, 5863651, 6027941, 6361351, 6796541

Offset

1,1

Comments

Primes p such that 3*p+8, 9*p+32, 27*p+104, 81*p+320, and 243*p+968 are also primes. - Vincenzo Librandi, Aug 05 2010

Links

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

Formula

a(n) == 31 (mod 70). - John Cerkan, Oct 11 2016

Mathematica

Select[Prime[Range[500000]], And@@PrimeQ[Rest[NestList[3#+8&, #, 5]]]&] (* Harvey P. Dale, Apr 07 2014 *)

Prog

(Magma) [n: n in [1..25000000] | IsPrime(n) and IsPrime(3*n+8) and IsPrime(9*n+32) and IsPrime(27*n+104) and IsPrime(81*n+320) and IsPrime(243*n+968)] // Vincenzo Librandi, Aug 05 2010
(PARI) is(n)=isprime(n) && isprime(3*n+8) && isprime(9*n+32) && isprime(27*n+104) && isprime(81*n+320) && isprime(243*n+968) \\ Charles R Greathouse IV, Oct 11 2016

Crossrefs

Subsequence of A023210, A023248, A023279, and A023309.

Sequence in context: A345858 A129472 A023309 * A236131 A205034 A205282

Adjacent sequences: A023334 A023335 A023336 * A023338 A023339 A023340

Keyword

nonn

Author

David W. Wilson

Status

approved