|
Search: id:A072302
|
|
|
| A072302 |
|
Number of positive integers not exceeding n that are relatively prime to phi(n). |
|
+0
1
|
|
| 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
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
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: A064515 A112754 A045864 this_sequence A116513 A122651 A130535
Adjacent sequences: A072299 A072300 A072301 this_sequence A072303 A072304 A072305
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Jul 14 2002
|
|
|
Search completed in 0.002 seconds
|
