cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A066840 Sum of positive integers k where k <= n/2 and gcd(k,n) = 1.

Table of values

n a(n)
1 0
2 1
3 1
4 1
5 3
6 1
7 6
8 4
9 7
10 4
11 15
12 6
13 21
14 9
15 14
16 16
17 36
18 13
19 45
20 20
21 30
22 25
23 66
24 24
25 63
26 36
27 61
28 42
29 105
30 32
31 120
32 64
33 80
34 64
35 102
36 54
37 171
38 81
39 114
40 80
41 210
42 66
43 231
44 110
45 134
46 121
47 276
48 96
49 258
50 124
51 200
52 156
53 351
54 121
55 270
56 168
57 252
58 196
59 435
60 120
61 465
62 225
63 282

List of values

[0, 1, 1, 1, 3, 1, 6, 4, 7, 4, 15, 6, 21, 9, 14, 16, 36, 13, 45, 20, 30, 25, 66, 24, 63, 36, 61, 42, 105, 32, 120, 64, 80, 64, 102, 54, 171, 81, 114, 80, 210, 66, 231, 110, 134, 121, 276, 96, 258, 124, 200, 156, 351, 121, 270, 168, 252, 196, 435, 120, 465, 225, 282]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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