A072302 Number of positive integers not exceeding n that are relatively prime to phi(n).

1, 2, 2, 2, 3, 3, 3, 4, 3, 5, 5, 6, 5, 5, 8, 8, 9, 6, 7, 10, 7, 9, 11, 12, 10, 9, 9, 9, 13, 15, 9, 16, 14, 17, 12, 12, 13, 13, 13, 20, 17, 14, 13, 18, 15, 21, 23, 24, 14, 20, 26, 17, 25, 18, 22, 19, 19, 25, 29, 30, 17, 17, 21, 32, 22, 26, 21, 34, 32, 23, 25, 24, 25, 25, 30, 25, 21

Offset

1,2

Links

Table of n, a(n) for n=1..77.

Example

Among the positive integers not exceeding 12, the six numbers 1,3,5,7,9,11 are relatively prime to phi(12)=4. Hence a(12)=6.

Mathematica

r = {}; Do[s = EulerPhi[n]; j = 0; For[i = 1, i <= n, i++, If[GCD[s, i] == 1, j++ ]]; r = Append[r, j], {n, 1, 10^2}]; r

Crossrefs

Sequence in context: A112754 A283467 A045864 * A369715 A165360 A340542

Adjacent sequences: A072299 A072300 A072301 * A072303 A072304 A072305

Keyword

nonn

Author

Joseph L. Pe, Jul 14 2002

Status

approved