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%I #11 Apr 07 2022 10:55:15
%S 1,1,1,1,1,2321204055,37185086099807
%N a(n) is the smallest number m such that m^(2^k) + 2^(2^k) is prime for k=0,1,...,n.
%C The first five terms of this sequence correspond to Fermat primes.
%C According to the answers to Prime Puzzle 399 (see link), a(6) is larger than 2.3*10^12. - _M. F. Hasler_, Aug 02 2007
%H Carlos Rivera (ed.), <a href="http://primepuzzles.net/puzzles/puzz_399.htm">Puzzle 399. Some more terms</a>, The Prime Puzzles and Problems Connection.
%e a(5)=2321204055 because 2321204055 is the smallest number m such that m^(2^k) + 2^(2^k) is prime for k=0,1,2,3,4 and 5.
%Y Cf. A090872, A090873, A090874.
%K nonn
%O 0,6
%A _Farideh Firoozbakht_, Feb 06 2004
%E a(6) found by Kellen Shenton sent in by _Jeppe Stig Nielsen_, Apr 06 2022