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A023285
Primes that remain prime through 3 iterations of function f(x) = 5x + 6.
3
7, 79, 181, 233, 359, 401, 449, 1009, 1093, 1259, 1303, 1373, 1511, 1931, 2011, 2339, 2477, 3019, 3691, 4349, 4409, 5417, 5879, 6301, 6553, 6637, 7079, 8329, 9127, 9137, 10303, 10499, 11579, 12391, 13259, 14251, 15101, 15107, 15217, 15329, 15527, 15679
OFFSET
1,1
COMMENTS
Primes p such that 5*p+6, 25*p+36 and 125*p+186 are also primes. - Vincenzo Librandi, Aug 04 2010
MATHEMATICA
p3Q[n_]:=And@@PrimeQ/@NestList[5#+6&, n , 3]; Select[Prime[Range[2000]], p3Q] (* Harvey P. Dale, Feb 20 2011 *)
PROG
(Magma) [n: n in [1..150000] | IsPrime(n) and IsPrime(5*n+6) and IsPrime(25*n+36) and IsPrime(125*n+186)] // Vincenzo Librandi, Aug 04 2010
CROSSREFS
Subsequence of A023219, A023254, and of A081759.
Sequence in context: A065902 A140613 A139945 * A135051 A201860 A176130
KEYWORD
nonn
STATUS
approved