%I #6 Jun 10 2016 22:10:11
%S 1,4,6,9,12,15,18,21,34,36,75,102,231,256,309,513,748,3789,12378,36378
%N Numbers n such that 6^n + 5^(n+1) is prime.
%C a(21) > 10^5.
%t Select[Range[0,100000], PrimeQ[6^n + 5^(n + 1)] &]
%o (PARI) is(n)=ispseudoprime(6^n + 5^(n+1)) \\ _Charles R Greathouse IV_, Jun 10 2016
%o (PFGW) ABC2 6^$a + 5^($a+1)
%o a: from 1 to 100000
%o _Charles R Greathouse IV_, Jun 10 2016
%Y Cf. A093765.
%K nonn,more
%O 1,2
%A _Robert Price_, Jun 10 2016