A145487 - OEIS

%I #9 Dec 20 2022 12:13:43

%S 0,1,2,3,4,7,8,9,11,14,16,21,22,24,29,32,37,38,42,43,46,51,58,63,64,

%T 66,71,73,77,79,81,84,92,98,99,102,106,107,108,113,119,123,134,136,

%U 142,143,156,157,158,162,184,191,196,198,203,212,217,219,227,228,238,241,246

%N Numbers k such that 6k+5 is prime and 12k+5 is also prime

%H Ivan Neretin, <a href="/A145487/b145487.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = (A145471(n)-5)/12.

%t aa = {}; k = 5; Do[If[PrimeQ[(k + Prime[n])/2], AppendTo[aa, (Prime[n] - 5)/12]], {n, 1, 500}]; aa

%t Select[Range[0, 250], PrimeQ[6 # + 5] && PrimeQ[12 # + 5] &] (* _Ivan Neretin_, Jan 21 2017 *)

%t Select[Range[0,250],AllTrue[5+{6#,12#},PrimeQ]&] (* _Harvey P. Dale_, Dec 20 2022 *)

%Y Cf. A063908-A063913, A092109, A145471-A145490.

%K nonn

%O 1,3

%A _Artur Jasinski_, Oct 11 2008