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Numbers n such that the n-th Fibonacci number is prime, but cannot be written in the form a^2 + 10*b^2.
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%I #12 May 02 2013 13:09:34

%S 3,4,5,7,13,17,23,29,43,47,83,137,433,449,509,569,571,2971,4723,5387,

%T 9677,14431,30757,50833,104911,201107,433781,604711,931517,1049897,

%U 1285607,1636007

%N Numbers n such that the n-th Fibonacci number is prime, but cannot be written in the form a^2 + 10*b^2.

%H Blair Kelly, <a href="http://mersennus.net/fibonacci">Factorizations of Fibonacci and Lucas numbers</a>

%Y Cf. A000045, A001605.

%K nonn

%O 1,1

%A _V. Raman_, Sep 08 2012