A023290 Primes that remain prime through 3 iterations of function f(x) = 7x + 6.

149, 439, 1319, 2069, 2089, 2389, 2699, 2819, 4259, 4919, 5059, 5689, 6469, 7559, 8429, 8669, 9199, 9239, 9319, 9769, 10159, 10529, 14449, 14479, 17659, 18899, 19289, 23879, 25189, 29819, 33119, 33149, 34159, 34439, 35089, 36229, 38839, 39829, 40699

Offset

1,1

Comments

Primes p such that 7*p+6, 49*p+48 and 343*p+342 are primes. - Vincenzo Librandi, Aug 04 2010

Links

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

Formula

a(n) == 9 (mod 10). - John Cerkan, Sep 23 2016

Prog

(Magma) [n: n in [1..150000] | IsPrime(n) and IsPrime(7*n+6) and IsPrime(49*n+48) and IsPrime(343*n+342)]; // Vincenzo Librandi, Aug 04 2010

Crossrefs

Subsequence of A023225, A023259, and A024900.

Sequence in context: A216312 A112859 A141980 * A142629 A078849 A078950

Adjacent sequences: A023287 A023288 A023289 * A023291 A023292 A023293

Keyword

nonn

Author

David W. Wilson

Status

approved