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A023318 Numbers n such that n remains prime through 4 iterations of function f(x) = 7x + 6. 2
1319, 2699, 4259, 4919, 5689, 8669, 10159, 10529, 29819, 33119, 82339, 86689, 98669, 174079, 177949, 196739, 207869, 210599, 222499, 231809, 253369, 267299, 275699, 323699, 362459, 371639, 378179, 388529, 397799, 402529, 421079, 448859, 468499 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

n, 7*n+6, 49*n+48, 343*n+342 and 2401*n+2400 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, Oct 08 2016

PROG

(MAGMA) [n: n in [1..1000000] | IsPrime(n) and IsPrime(7*n+6) and IsPrime(49*n+48) and IsPrime(343*n+342) and IsPrime(2401*n+2400)] // Vincenzo Librandi, Aug 04 2010

CROSSREFS

Subsequence of A023225, A023259, A023290, and A024900.

Sequence in context: A241962 A200202 A255799 * A066663 A067206 A248857

Adjacent sequences:  A023315 A023316 A023317 * A023319 A023320 A023321

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)