cp's OEIS Frontend

A300407 Primes of the form 17*2^n + 1.

%I A300407 #23 Sep 08 2022 08:46:20
%S A300407 137,557057,2281701377,38280596832649217,
%T A300407 3032901347000164747248857685080177164813336577,
%U A300407 240291200809860268823328460101036918152537809975084178304538443375796289537,4031417378886400659867047414062478199819447786118941877597755244819503521544011777
%N A300407 Primes of the form 17*2^n + 1.
%C A300407 For the corresponding exponents n see A002259.
%H A300407 Ray Ballinger, Wilfried Keller, <a href="http://www.prothsearch.com/riesel1.html">List of primes k*2^n + 1 for k < 300</a>.
%e A300407 From _Muniru A Asiru_, Mar 29 2018: (Start)
%e A300407 137 is a member because 17 * 2^3 + 1 = 137 which is a prime.
%e A300407 557057 is a member because 17 * 2^15 + 1 = 557057 which is a prime.
%e A300407 2281701377 is a member because 17 * 2^27 + 1 = 2281701377 which is a prime.
%e A300407 ... (End)
%p A300407 a:=(n,k)->`if`(isprime(k*2^n+1), k*2^n+1, NULL):
%p A300407 seq(a(n,17), n=1..267);
%t A300407 Select[Table[17 2^n + 1, {n, 400}], PrimeQ] (* _Vincenzo Librandi_, Mar 07 2018 *)
%o A300407 (GAP) Filtered(List([1..270],n->17*2^n + 1),IsPrime); # _Muniru A Asiru_, Mar 06 2018
%o A300407 (Magma) [a: n in [1..300] | IsPrime(a) where a is 17*2^n + 1]; // _Vincenzo Librandi_, Mar 07 2018
%o A300407 (PARI) lista(nn) = {for(k=1, nn, if(ispseudoprime(p=17*2^k+1), print1(p, ", ")));} \\ _Altug Alkan_, Mar 28 2018
%Y A300407 Cf. A002259, A019434, A039687, A050527, A050528, A050529, A195745, A291049, A050526, A300406, A300408.
%K A300407 nonn
%O A300407 1,1
%A A300407 _Martin Renner_, Mar 05 2018