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%I #8 Aug 30 2024 22:11:02
%S 2,5,1597,229265413057075367692743352179590077832064383222590237
%N Fibonacci-Fermat numbers.
%C a(4) = 1184388169...3238828317 has 13697 decimal digits. - _Alois P. Heinz_, Aug 30 2024
%F a(n) = Fibonacci(2^(2^n)+1) = A000045(A000215(n)).
%o (PARI) a(n)=fibonacci(2^(2^n)+1)
%Y Cf. A000045, A000215.
%K nonn
%O 0,1
%A _Jorge Coveiro_, Dec 24 2004