%I
%S 6,60,66,126,150,156,186,204,246,276,306,324,330,384,390,480,504,546,
%T 594,606,684,774,786,840,870,876,900,936,966,1044,1050,1080,1176,1260,
%U 1266,1320,1326,1434,1476,1494,1500,1530,1596,1650,1674,1710,1914,1956
%N Numbers n such that 7*n+1 are prime.
%H Vincenzo Librandi, <a href="/A173904/b173904.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[2000], PrimeQ[7 # + 1]&& PrimeQ[7 #  1]&] (* _Vincenzo Librandi_, Apr 05 2013 *)
%o (MAGMA) [n: n in [1..2000]  IsPrime(7*n+1) and IsPrime(7*n1)]
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Mar 08 2010
