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Primes of the form 3^p-2^(p+1), where p is also a prime.
2

%I #7 Sep 08 2022 08:45:46

%S 11,179,1931,617669101316651,14130386090585813000157964091,

%T 19088056323407826758511836230558252318494847619

%N Primes of the form 3^p-2^(p+1), where p is also a prime.

%C The next term has 1117 digits and is not included explicitly for that reason.

%F a(n) = 3^A162714(n)-2^(1+A162714(n)) .

%t Select[Table[3^p - 2^(p + 1), {p, Prime[Range[70]]}], PrimeQ] (* _Vincenzo Librandi_, Sep 11 2013 *)

%o (Magma) [a: p in PrimesInInterval(3,1200) | IsPrime(a) where a is 3^p - 2^(p + 1)]; // _Vincenzo Librandi_, Sep 11 2013

%Y Cf. A162714.

%K nonn

%O 1,1

%A _Vincenzo Librandi_, Jul 11 2009

%E Clarified status of p in the definition - _R. J. Mathar_, Oct 16 2009