%I #18 Sep 27 2024 05:38:07

%S 1,5,7,11,13,17,23,25,35,37,47,55,61,73,77,83,91,95,101,103,107,121,

%T 125,131,143,151,161,173,175,187,205,217,221,233,245,257,263,271,277,

%U 287,305,311,325,331,347,367,373,391,395,425,443,451,455,461,481,503,551

%N Numbers k such that 6+k and 6*k+1 are prime.

%C All terms == 1 or 5 (mod 6). - _Robert Israel_, Oct 29 2020

%H Robert Israel, <a href="/A120222/b120222.txt">Table of n, a(n) for n = 1..10000</a>

%p select(n -> isprime(n+6) and isprime(6*n+1), [seq(i,i=1..1000,2)]); # _Robert Israel_, Oct 29 2020

%t Select[Range[551],PrimeQ[#+6]&&PrimeQ[6#+1]&] (* _James C. McMahon_, Sep 26 2024 *)

%Y Cf. A120226, A120227, A120228, A106057-A106066.

%K nonn

%O 1,2

%A _Zak Seidov_, Jun 10 2006