login
A162715
Primes of the form 3^p-2^(p+1), where p is also a prime.
2
11, 179, 1931, 617669101316651, 14130386090585813000157964091, 19088056323407826758511836230558252318494847619
OFFSET
1,1
COMMENTS
The next term has 1117 digits and is not included explicitly for that reason.
FORMULA
a(n) = 3^A162714(n)-2^(1+A162714(n)) .
MATHEMATICA
Select[Table[3^p - 2^(p + 1), {p, Prime[Range[70]]}], PrimeQ] (* Vincenzo Librandi, Sep 11 2013 *)
PROG
(Magma) [a: p in PrimesInInterval(3, 1200) | IsPrime(a) where a is 3^p - 2^(p + 1)]; // Vincenzo Librandi, Sep 11 2013
CROSSREFS
Cf. A162714.
Sequence in context: A101791 A140034 A363024 * A131638 A157382 A174979
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Jul 11 2009
EXTENSIONS
Clarified status of p in the definition - R. J. Mathar, Oct 16 2009
STATUS
approved