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%I #22 Dec 03 2024 16:59:45
%S 3,17,328256958598444055417,127173474823342767533669605649
%N Primes of the form 3^p-2^p-2 generated from primes p.
%C a(5) has 4816 digits.
%t lst={}; Do[p=Prime[n]; If[PrimeQ[r=3^p - 2^p - 2], AppendTo[lst, r]], {n, 1000}]; lst (* _Vincenzo Librandi_, Sep 25 2015 *)
%t Select[3^#-2^#-2&/@Prime[Range[50]],PrimeQ] (* _Harvey P. Dale_, Dec 03 2024 *)
%o (Magma) [3^p-2^p-2: p in PrimesUpTo(4000) | IsPrime(3^p-2^p-2)]; // _Vincenzo Librandi_, Sep 25 2015
%Y Cf. A162712 (associated p).
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Jul 11 2009
%E Edited by _R. J. Mathar_, Jul 26 2009