A023265 Primes that remain prime through 2 iterations of function f(x) = 9x + 2.

3, 11, 19, 31, 103, 109, 113, 131, 151, 173, 179, 239, 283, 313, 491, 521, 599, 619, 733, 739, 773, 929, 1019, 1103, 1361, 1439, 1481, 1621, 1709, 1741, 1831, 1993, 2083, 2153, 2293, 2411, 2549, 2551, 2593, 2689, 2741, 2819, 2843, 2969, 3001, 3623, 3931, 4001

Offset

1,1

Comments

Primes p such that 9*p+2 and 81*p+20 are also primes. - Vincenzo Librandi, Aug 04 2010

Links

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

Prog

(Magma) [n: n in [1..100000] | IsPrime(n) and IsPrime(9*n+2) and IsPrime(81*n+20)] // Vincenzo Librandi, Aug 04 2010

Crossrefs

Subsequence of A023233.

Sequence in context: A175122 A031369 A014223 * A018557 A270528 A213540

Adjacent sequences: A023262 A023263 A023264 * A023266 A023267 A023268

Keyword

nonn

Author

David W. Wilson

Status

approved