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%I #4 Aug 07 2019 14:45:32
%S 7,463,35839,798167678837469920188160718521149336927,
%T 24665899002341798194980052306171212216360861465143461865961807325057879,
%U 5001149050738853423183653309332375420192266379562546200601855155172715420590196078603421469034502777938287
%N Primes of form (3^n + 2^n)/5.
%C Numbers n such that (2^n + 3^n)/5 is prime are listed in A057469 = {3, 7, 11, 83, 149, 223, 599, 647, 1373, 8423, ...}.
%F a(n) = (2^A057469(n) + 3^A057469(n))/5.
%t Do[f=(2^n+3^n)/5; If[PrimeQ[f], Print[{n, f}]], {n, 1, 1000}]
%t Select[Table[(3^n+2^n)/5,{n,500}],PrimeQ] (* _Harvey P. Dale_, Aug 07 2019 *)
%Y Cf. A057469.
%K nonn
%O 1,1
%A _Alexander Adamchuk_, Feb 05 2007