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%I #27 Nov 08 2023 07:48:05
%S 17,19,23,31,47,79,271,1039,2063,4111,32783,65551,4194319,8388623,
%T 67108879,1073741839,4294967311,1099511627791,4398046511119,
%U 70368744177679,2305843009213693967,4722366482869645213711,75557863725914323419151
%N Primes of the form 2^k + 15.
%H Vincenzo Librandi, <a href="/A144487/b144487.txt">Table of n, a(n) for n = 1..37</a>
%F a(n) = 2^A057197(n) + 15. - _Elmo R. Oliveira_, Nov 08 2023
%t Select[2^Range[0,200]+15,PrimeQ] (* _Vladimir Joseph Stephan Orlovsky_, Feb 03 2012 *)
%t Select[Table[2^n + 15, {n, 1, 300}], PrimeQ] (* _Vincenzo Librandi_, Feb 23 2014 *)
%o (PARI) {for(n=0, 72, if(isprime(k=2^n+15), print1(k, ",")))}
%o (Magma)[a: n in [1..100] | IsPrime(a) where a is 2^n+15]; // _Vincenzo Librandi_, Feb 23 2014
%Y Cf. A000040, A057197 (numbers k such that 2^k + 15 is prime). [From _Klaus Brockhaus_, Dec 11 2008]
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Dec 09 2008
%E Edited by _Klaus Brockhaus_ and _R. J. Mathar_, Dec 10 2008
%E Definition simplified by _Jon E. Schoenfield_, Jun 17 2010
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