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A049810 a(n)=number of Farey fractions of order n that are <=1/6; cf. A049805. 9
1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14, 16, 17, 20, 22, 24, 26, 29, 30, 34, 36, 39, 41, 45, 46, 51, 54, 58, 61, 65, 67, 73, 76, 80, 82, 88, 90, 97, 101, 105, 109, 116, 119, 126, 129, 135, 139, 147, 150, 158, 162, 168, 173, 182 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..59.

MATHEMATICA

Farey[n_] := Union[Flatten[Join[{0}, Table[a/b, {b, n}, {a, b}]]]]; f[n_] := Length@ Select[ Farey@ n, # <= 1/6 &]; Array[f, 59] (* Robert G. Wilson v, Nov 14 2012 *)

CROSSREFS

Cf. A005728, A049806, A049807, A049808, A049809, A049811, A049812, A049813, A049814.

Sequence in context: A033106 A119485 A058363 * A132018 A334142 A044919

Adjacent sequences:  A049807 A049808 A049809 * A049811 A049812 A049813

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified September 21 08:38 EDT 2020. Contains 337268 sequences. (Running on oeis4.)