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%I #20 Sep 08 2022 08:44:47
%S 11,31,211,1151,3181,5051,5261,6101,6661,9391,9551,10501,11701,13171,
%T 15901,16481,19531,22051,24181,26261,27031,28351,28591,28661,29411,
%U 30941,31321,32621,38011,40471,42101,48371,49921,57571,59791,61981,66161,67271
%N Primes that remain prime through 3 iterations of function f(x) = 3x + 8.
%C Primes p such that 3*p+8, 9*p+32 and 27*p+104 are also primes. - _Vincenzo Librandi_, Aug 04 2010
%H John Cerkan, <a href="/A023279/b023279.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) == 1 (mod 10). - _John Cerkan_, Sep 16 2016
%t Select[Prime@ Range@ 7000, Times @@ Boole@ PrimeQ@ Rest@ NestList[3 # + 8 &, #, 3] > 0 &] (* _Michael De Vlieger_, Sep 19 2016 *)
%o (Magma) [n: n in [1..150000] | IsPrime(n) and IsPrime(3*n+8) and IsPrime(9*n+32) and IsPrime(27*n+104)] // _Vincenzo Librandi_, Aug 04 2010
%o (PARI) is(n)=isprime(n) && isprime(3*n+8) && isprime(9*n+32) && isprime(27*n+104) \\ _Charles R Greathouse IV_, Sep 20 2016
%Y Subsequence of A023210 and of A023248.
%K nonn
%O 1,1
%A _David W. Wilson_
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