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A023321
Primes that remain prime through 4 iterations of function f(x) = 8x + 5.
2
8431, 9721, 24169, 35311, 63577, 74203, 109471, 109891, 140269, 174613, 176599, 182857, 210187, 241561, 270553, 274837, 274909, 276517, 281557, 324763, 326737, 383659, 464089, 474127, 489109, 498403, 540781, 563587, 576943, 582949, 633253
OFFSET
1,1
COMMENTS
Primes p such that 8*p+5, 64*p+45, 512*p+365 and 4096*p+2925 are also primes. - Vincenzo Librandi, Aug 04 2010
FORMULA
a(n) == 19 or 31 (mod 42). - John Cerkan, Oct 08 2016
PROG
(Magma) [n: n in [1..5000000] | IsPrime(n) and IsPrime(8*n+5) and IsPrime(64*n+45) and IsPrime(512*n+365) and IsPrime(4096*n+2925)] // Vincenzo Librandi, Aug 04 2010
CROSSREFS
Subsequence of A023230, A023262, A023293, and A105133.
Sequence in context: A237137 A208182 A093221 * A116258 A116311 A116351
KEYWORD
nonn
STATUS
approved