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%I #16 Sep 08 2022 08:46:19
%S 3,4,7,11,83,149,223,599,647,1373,8423
%N Numbers n such that (3^n - (-2)^n)/5 is prime.
%C a(12) > 65535. Presumably, a(12) = 149497 and a(13) = 388897.
%e 4 is in this sequence because (3^4 - (-2)^4)/5 = 13 is prime.
%t Select[Range[2000], PrimeQ[(3^# - (-2)^#)/5] &] (* _Michael De Vlieger_, Dec 09 2017 *)
%o (Magma) [n: n in [1..1000] | IsPrimePower((3^n-(-2)^n) div 5)];
%Y Supersequence A057469.
%Y Cf. A107036 (numbers n such that (2^n-(-1)^n)/3 is prime).
%K nonn,more
%O 1,1
%A _Juri-Stepan Gerasimov_, Sep 04 2017
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