A049814 a(n)=number of Farey fractions of order n that are <=1/10; cf. A049805.

1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 17, 18, 20, 21, 23, 24, 26, 27, 30, 32, 34, 36, 39, 40, 43, 45, 47, 49, 53, 54, 58, 60, 63, 65, 69, 70, 74, 76, 80, 83, 88, 90, 94, 97, 101, 104, 109, 110

Offset

1,10

Links

Table of n, a(n) for n=1..60.

Mathematica

Farey[n_] := Union[Flatten[Join[{0}, Table[a/b, {b, n}, {a, b}]]]]; f[n_] := Length@ Select[ Farey@ n, # <= 1/10 &]; Array[f, 60] (* Robert G. Wilson v, Nov 14 2012 *)

Crossrefs

Cf. A005728, A049806, A049807, A049808, A049809, A049810, A049811, A049812, A049813.

Sequence in context: A327749 A171828 A246450 * A028828 A334139 A178864

Adjacent sequences: A049811 A049812 A049813 * A049815 A049816 A049817

Keyword

nonn

Author

Clark Kimberling

Status

approved