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%I #19 Oct 21 2022 17:20:21
%S 1,919444,1059094,1951734,1963736
%N Numbers k such that k^(2^20) + 1 is prime (a generalized Fermat prime).
%H Chris K. Caldwell, <a href="https://primes.utm.edu/primes/page.php?id=123875">The Prime Database: 919444^1048576 + 1</a>
%H Chris K. Caldwell, <a href="https://primes.utm.edu/primes/page.php?id=125753">The Prime Database: 1059094^1048576 + 1</a>
%H Chris K. Caldwell, <a href="https://primes.utm.edu/primes/search.php?Description=%25%5E1048576%2B1%24&OnList=all&Number=200&Style=HTML">The Prime Database: ?^1048576 + 1</a>
%Y Cf. A056993, A005574, A000068, A006314, A006313, A006315, A006316, A056994, A056995, A057465, A057002, A088361, A088362, A226528, A226529, A226530, A251597, A253854, A244150, A243959.
%K nonn,hard,more
%O 1,2
%A _Jeppe Stig Nielsen_, Nov 04 2018
%E a(4) from _Jeppe Stig Nielsen_, Aug 31 2022
%E a(5) from _Jeppe Stig Nielsen_, Oct 21 2022