%I
%S 1,5,11,16,59,239,299,2524,2695,7657,14028
%N Numbers k such that 3*13^k  2 is prime.
%C The next terms are > 15000.  _Jinyuan Wang_, Feb 02 2020
%e 3(13^5)  2 = 1113877, which is a prime number, hence 5 is in the sequence.
%e 3(13^7)  2 = 188245549, but that is divisible by 211, hence 7 is NOT in the sequence.
%t Do[ If[ PrimeQ[ 3*13^n  2 ], Print[ n ] ], {n, 0, 1500} ] (* RGWv *)
%t Select[Range[0, 4000], PrimeQ[(3*13^#  2)] &] (* _Vincenzo Librandi_, Sep 28 2012 *)
%o (PARI) is(n)=ispseudoprime(3*13^n2) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A057871 (3*13^k + 2 is prime).
%K nonn,more
%O 1,2
%A _Robert G. Wilson v_, Nov 15 2000
%E a(8)a(9) from _Vincenzo Librandi_, Sep 28 2012
%E a(10) from _Bruno Berselli_, Sep 28 2012
%E a(11) from _Jinyuan Wang_, Feb 02 2020
