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%I #33 Sep 03 2013 17:10:53
%S 7,11,12,14,17,18,19,20,22,23,27,28,29,30,31,32,33,35,36,37,38,41,43,
%T 44,45,46,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,66,67,69,70,71,
%U 72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,90,91,92
%N Numbers that are not the product of two Fibonacci numbers (not necessarily distinct).
%C All primes except prime Fibonacci numbers are in this sequence.
%e Although 12 can be expressed as a product of Fibonacci numbers, it takes three of them, not two, hence 12 is in the list.
%e There is no way to express 14 as a product of Fibonacci numbers since its larger prime factor, 7, is not a Fibonacci number, hence 14 is in the list.
%e 16 is not in the list because it can be expressed as 2 * 8.
%t nn = 12; f = Fibonacci[Range[2, nn]]; f2 = Select[Union[Flatten[Outer[Times, f, f]]], # <= f[[-1]] &]; Complement[Range[f[[-1]]], f2] (* _T. D. Noe_, Sep 03 2013 *)
%Y Cf. A049997 (complement).
%K nonn,easy
%O 1,1
%A _Alonso del Arte_, Sep 02 2013
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