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A023319 Numbers n such that n remains prime through 4 iterations of function f(x) = 8x + 1. 2
2207, 126107, 230567, 366347, 590207, 788027, 831167, 919067, 985937, 1111427, 1154567, 1170857, 1367507, 1463597, 1624757, 1934417, 2034797, 2468027, 2502767, 2545307, 3019787, 3287027, 3385817, 3675197, 3692207, 4087757, 4565927, 4600577 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

n, 8*n+1, 64*n+9, 512*n+73 and 4096*n+585 are primes. - Vincenzo Librandi, Aug 04 2010

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

rp4Q[n_]:=AllTrue[Rest[NestList[8#+1&, n, 4]], PrimeQ]; Select[Prime[ Range[ 325000]], rp4Q] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 23 2014 *)

PROG

(MAGMA) [n: n in [1..5000000] | IsPrime(n) and IsPrime(8*n+1) and IsPrime(64*n+9) and IsPrime(512*n+73) and IsPrime(4096*n+585)] // Vincenzo Librandi, Aug 04 2010

CROSSREFS

Sequence in context: A004971 A037210 A114360 * A207793 A232074 A278207

Adjacent sequences:  A023316 A023317 A023318 * A023320 A023321 A023322

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified August 15 15:24 EDT 2020. Contains 336504 sequences. (Running on oeis4.)