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%I #25 Sep 08 2022 08:44:47
%S 5,7,11,19,29,47,61,71,79,89,97,107,127,131,139,151,167,179,181,211,
%T 229,251,271,317,337,397,401,419,421,449,461,467,487,541,547,557,571,
%U 599,601,607,659,677,701,709,727,739,761,811,827,839,877,881,907,929,971,1051
%N Primes p such that 9*p + 8 is also prime.
%H Charles R Greathouse IV, <a href="/A023235/b023235.txt">Table of n, a(n) for n = 1..10000</a>
%t lst={};Do[p=Prime[n];If[PrimeQ[9*p+8],AppendTo[lst,p]],{n,6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Mar 10 2009 *)
%t Select[Prime[Range[900]], PrimeQ[9 # + 8] &] (* _Vincenzo Librandi_, May 21 2014 *)
%o (Magma) [n: n in [0..1000] | IsPrime(n) and IsPrime(9*n+8)]; // _Vincenzo Librandi_, Nov 20 2010
%o (PARI) is(n)=isprime(9*n+8) && isprime(n) \\ _Charles R Greathouse IV_, Jul 02 2013
%o (Magma) [p: p in PrimesUpTo(1100)| IsPrime(9*p+8)]; // _Vincenzo Librandi_, May 21 2014
%K nonn,easy
%O 1,1
%A _David W. Wilson_
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