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A172996 Primes of form (3^n+7)/2. 2
5, 17, 1097, 304133393856678854559841996309430657 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = (3^A172995(n)+7)/2.
MATHEMATICA
Select[Table[(3^n + 7)/2, {n, 500}], PrimeQ] (* Vincenzo Librandi, Sep 24 2015 *)
PROG
(Magma) [a: n in [0..500] | IsPrime(a) where a is (3^n+7) div 2]; // Vincenzo Librandi, Sep 24 2015
(PARI) for(n=1, 1e3, if(isprime(k=(3^n+7)/2), print1(k", "))) \\ Altug Alkan Sep 24 2015
CROSSREFS
Cf. A172995.
Sequence in context: A218378 A119531 A248921 * A253624 A085832 A062223
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Feb 07 2010
STATUS
approved

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Last modified April 20 13:40 EDT 2024. Contains 371844 sequences. (Running on oeis4.)