%I #8 Nov 14 2012 10:11:43
%S 1,1,1,1,1,1,1,1,2,3,4,5,6,7,8,9,10,11,13,14,16,17,19,20,22,23,25,27,
%T 30,31,34,36,38,40,43,44,48,50,53,55,59,60,64,66,69,72,77,79,84,86,90,
%U 93,98,100,105,108,112,115,121,122
%N a(n)=number of Farey fractions of order n that are <=1/9; cf. A049805.
%t Farey[n_] := Union[Flatten[Join[{0}, Table[a/b, {b, n}, {a, b}]]]]; f[n_] := Length@ Select[ Farey@ n, # <= 1/9 &]; Array[f, 60] (* _Robert G. Wilson v_, Nov 14 2012 *)
%Y Cf. A005728, A049806, A049807, A049808, A049809, A049810, A049811, A049812, A049814.
%K nonn
%O 1,9
%A _Clark Kimberling_
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