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A023291 Primes that remain prime through 3 iterations of function f(x) = 8x + 1. 2
2, 1487, 2207, 2927, 8807, 11117, 16187, 17657, 26357, 44927, 45377, 48497, 91757, 110237, 117167, 122327, 125387, 126107, 145007, 170927, 174527, 190787, 193847, 203897, 230567, 244247, 246017, 270287, 280547, 283937, 347957, 362237, 364337 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Primes p such that 8*p+1, 64*p+9 and 512*p+73 are also primes. - Vincenzo Librandi, Aug 04 2010
LINKS
FORMULA
a(n) == 17 (mod 30) for n > 1. - John Cerkan, Sep 23 2016
MATHEMATICA
okQ[n_]:=And@@PrimeQ[NestList[8#+1&, n, 3]]; Select[Prime[Range[50000]], okQ] (* Harvey P. Dale, Jan 09 2011 *)
PROG
(Magma) [n: n in [1..450000] | IsPrime(n) and IsPrime(8*n+1) and IsPrime(64*n+9) and IsPrime(512*n+73)] // Vincenzo Librandi, Aug 04 2010
CROSSREFS
Subsequence of A005123, A023228, and A023260.
Sequence in context: A374193 A172234 A339543 * A319329 A058423 A233906
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified July 13 17:30 EDT 2024. Contains 374284 sequences. (Running on oeis4.)