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%I #21 Jul 24 2024 07:41:10
%S 38,58,64,144,198,324,950,1230,1934,4662,7644,9060,10852,11082,13740,
%T 16682,24502,27574,54940,66710,84402
%N Numbers k such that (2^127-1)*2^k + 1 is prime.
%C a(17) > 22800. - _Jinyuan Wang_, Mar 19 2020
%C a(19) > 30000. - _Tyler NeSmith_, Apr 12 2022
%o (PARI) is(n)=ispseudoprime((2^127-1)*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%K nonn,more
%O 1,1
%A _Pierre CAMI_, Sep 25 2004
%E a(15)-a(16) from _Jinyuan Wang_, Mar 19 2020
%E a(17)-a(18) from _Tyler NeSmith_, Apr 12 2022
%E a(19)-a(20) from _Michael S. Branicky_, Apr 22 2023
%E a(21) from _Michael S. Branicky_, Jul 23 2024