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%I #10 Sep 08 2022 08:45:44
%S 17,19,31,271,65551,4294967311
%N Primes of the form 2^(2^k)+15.
%C Fermat primes of order 15.
%C The number of Fermat primes of order 15 exceeds the number of known Fermat primes.
%C Terms given correspond to n= 0, 1, 2, 3, 4 and 5.
%C Next term >= 2^2^16 + 15. - _Vincenzo Librandi_, Jun 07 2016
%C Next term >= 2^2^17 + 15. - _Charles R Greathouse IV_, Jun 07 2016
%F Intersection of the primes and the set of Fermat numbers F(k,m) = 2^(2^k)+m of order m=15.
%e For k = 5, 2^32 + 15 = 4294967311 is prime.
%t Select[Table[2^(2^n) + 15, {n, 0, 10}], PrimeQ] (* _Vincenzo Librandi_, Jun 07 2016 *)
%o (PARI) g(n,m) = for(x=0,n,y=2^(2^x)+m;if(ispseudoprime(y),print1(y",")))
%o (Magma) [a: n in [0..15] | IsPrime(a) where a is 2^(2^n)+15]; // _Vincenzo Librandi_, Jun 07 2016
%Y Cf. A019434 (order 1), A104067 (superset for order 13), A160028 (order 81).
%Y Cf. similar sequences listed in A273547.
%K nonn
%O 1,1
%A _Cino Hilliard_, Apr 30 2009
%E Edited by _R. J. Mathar_, May 08 2009
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