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%I A125272 #17 Sep 08 2022 08:45:28
%S A125272 3,5,7,13,23,37,43,103,127,163,167,257,293,313,337,433,523,757,797,
%T A125272 887,953,1013,1063,1153,1283,1303,1307,1483,1597,1657,1667,1693,1723,
%U A125272 1783,1913,2003,2333,2347,2557,2897,2927,3067,3533,3823,3943,4003,4013,4093
%N A125272 Primes p such that 3p - 2 and 3p + 2 are also primes.
%H A125272 Charles R Greathouse IV, <a href="/A125272/b125272.txt">Table of n, a(n) for n = 1..10000</a>
%F A125272 a(n) = A125215(n)/3.
%t A125272 lst={}; Do[p=Prime[n]; If[PrimeQ[3*p-2]&&PrimeQ[3*p+2],AppendTo[lst,p]],{n,7!}]; lst (* _Vladimir Joseph Stephan Orlovsky_, Jan 18 2009 *)
%t A125272 Select[Prime[Range[600]],AllTrue[3#+{2,-2},PrimeQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, May 29 2021 *)
%o A125272 (Magma) [p: p in PrimesUpTo(70000)| IsPrime(3*p-2)and IsPrime(3*p+2)] // _Vincenzo Librandi_, Jan 29 2011
%o A125272 (PARI) is(n)=isprime(3*n-2)&&isprime(3*n+2)&&isprime(n) \\ _Charles R Greathouse IV_, Jul 02 2013
%Y A125272 Intersection of A023208 and A088878.
%Y A125272 Cf. A125215.
%K A125272 nonn,easy
%O A125272 1,1
%A A125272 _Zak Seidov_, Nov 26 2006

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