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%I #18 Sep 08 2022 08:45:12
%S 2,3,7,17,19,47,53,59,67,103,113,127,157,239,269,283,313,379,383,397,
%T 449,467,577,613,617,647,823,829,907,929,977,1097,1123,1279,1373,1447,
%U 1489,1523,1697,1723,1789,1877,1933,2017,2027,2063,2069,2237,2339,2423
%N Primes p such that 6*p-5 and 6*p-1 are primes.
%H Vincenzo Librandi, <a href="/A089144/b089144.txt">Table of n, a(n) for n = 1..4000</a>
%e 6*7=42, 42-5=37, 42-1=41, 37 and 41 primes.
%t okQ[n_]:=Module[{x=6n},PrimeQ[x-1]&&PrimeQ[x-5]]; Select[Prime[Range[ 500]],okQ] (* _Harvey P. Dale_, May 25 2011 *)
%t Select[Prime[Range[400]], PrimeQ[6 # - 5] && PrimeQ[6 # - 1]&] (* _Vincenzo Librandi_, May 23 2017 *)
%o (Magma) [p: p in PrimesUpTo(3000) |IsPrime(6*p-5) and IsPrime(6*p-1)]; // _Vincenzo Librandi_, May 23 2017
%Y Cf. A090606, A090607, A090608, A090609, A090610.
%K easy,nonn
%O 1,1
%A _Pierre CAMI_, Dec 05 2003
%E More terms from _Ray Chandler_, Dec 06 2003