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%I #33 Sep 08 2022 08:44:58
%S 11,41,641,40961,163841,167772161,2748779069441,180143985094819841,
%T 188894659314785808547841,193428131138340667952988161,
%U 850705917302346158658436518579420528641
%N Primes of form 5*2^n+1.
%C All terms are odd since if n is even, then 5*2^n+1 is divisible by 3. - _Michele Fabbrini_, Jun 06 2021
%H Muniru A Asiru, <a href="/A050526/b050526.txt">Table of n, a(n) for n = 1..12</a>
%H Ray Ballinger, Wilfried Keller, <a href="http://www.prothsearch.com/riesel1.html">List of primes k*2^n + 1 for k < 300</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Proth%27s_theorem">Proth's theorem</a>
%H <a href="/index/Pri#riesel">Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime</a>
%F a(n) = A083575(A002254(n)). - _Michel Marcus_, Mar 29 2018
%p a:=(n, k)->`if`(isprime(k*2^n+1), k*2^n+1, NULL):
%p seq(a(n, 5), n=1..127); # _Martin Renner_, Mar 05 2018
%o (Magma) [a: n in [1..200] | IsPrime(a) where a is 5*2^n + 1]; // _Vincenzo Librandi_, Mar 06 2018
%o (GAP) Filtered(List([1..270], n->5*2^n + 1), IsPrime); # _Muniru A Asiru_, Mar 06 2018
%o (PARI) lista(nn) = {for(k=1, nn, if(ispseudoprime(p=5*2^k+1), print1(p, ", "))); } \\ _Altug Alkan_, Mar 29 2018
%Y For the corresponding exponents n see A002254.
%Y Cf. A019434, A039687, A050527, A050528, A050529, A195745, A300406, A300407, A300408.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Dec 29 1999
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