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Primes that remain prime through 2 iterations of function f(x) = 8x + 7.
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%I #25 Sep 08 2022 08:44:47

%S 2,5,107,137,179,197,227,359,419,617,659,839,977,1097,1217,1409,1487,

%T 1559,1637,2087,2339,2447,2549,2609,2687,2909,2957,3167,3299,3467,

%U 3719,4139,4409,4787,4919,4937,5147,5189,5279,5639,6047,6269,7229,7547,7949

%N Primes that remain prime through 2 iterations of function f(x) = 8x + 7.

%C Primes p such that 8*p+7 and 64*p+63 are also primes. - _Vincenzo Librandi_, Aug 04 2010

%H Harvey P. Dale, <a href="/A023263/b023263.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[1100]],And@@PrimeQ[NestList[8#+7&,#,2]]&] (* _Harvey P. Dale_, Jul 22 2013 *)

%o (Magma) [n: n in [1..100000] | IsPrime(n) and IsPrime(8*n+7)and IsPrime(64*n+63)] // _Vincenzo Librandi_, Aug 04 2010

%K nonn

%O 1,1

%A _David W. Wilson_