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A023285 Numbers n such that n remains 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that n, 5*n+6, 25*n+36 and 125*n+186 are primes. - Vincenzo Librandi, Aug 04 2010

LINKS

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

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

Adjacent sequences:  A023282 A023283 A023284 * A023286 A023287 A023288

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified September 29 07:08 EDT 2020. Contains 337425 sequences. (Running on oeis4.)