%I A090875
%S A090875 1,1,1,1,1,2321204055
%N A090875 a(n) is the smallest number m such that m^(2^k) + 2^(2^k) is prime for 
               k=0,1,...,n.
%C A090875 The first five terms of this sequence correspond to Fermat primes.
%C A090875 According to the answers to Prime Puzzle 399 (see link), next term is 
               larger than 2.3*10^12. - M. F. Hasler (maximilian.Hasler(AT)gmail.com), 
               Aug 02 2007
%H A090875 C. Rivera (ed.), <a href="http://primepuzzles.net/puzzles/puzz_399.htm">
               Prime Puzzle # 399</a>.
%e A090875 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 A090875 Cf. A090872, A090873, A090874.
%Y A090875 Sequence in context: A017472 A017604 A022240 this_sequence A132907 A038685 
               A017289
%Y A090875 Adjacent sequences: A090872 A090873 A090874 this_sequence A090876 A090877 
               A090878
%K A090875 nonn
%O A090875 0,6
%A A090875 Farideh Firoozbakht (f.firoozbakht(AT)sci.ui.ac.ir), Feb 06 2004