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.

A328258 a(n) = Sum_{d|n, gcd(d,n/d) = 1} (-1)^(d + 1) * d.

Table of values

n a(n)
1 1
2 -1
3 4
4 -3
5 6
6 -4
7 8
8 -7
9 10
10 -6
11 12
12 -12
13 14
14 -8
15 24
16 -15
17 18
18 -10
19 20
20 -18
21 32
22 -12
23 24
24 -28
25 26
26 -14
27 28
28 -24
29 30
30 -24
31 32
32 -31
33 48
34 -18
35 48
36 -30
37 38
38 -20
39 56
40 -42
41 42
42 -32
43 44
44 -36
45 60
46 -24
47 48
48 -60
49 50
50 -26
51 72
52 -42
53 54
54 -28
55 72
56 -56
57 80
58 -30
59 60
60 -72
61 62
62 -32
63 80
64 -63
65 84

List of values

[1, -1, 4, -3, 6, -4, 8, -7, 10, -6, 12, -12, 14, -8, 24, -15, 18, -10, 20, -18, 32, -12, 24, -28, 26, -14, 28, -24, 30, -24, 32, -31, 48, -18, 48, -30, 38, -20, 56, -42, 42, -32, 44, -36, 60, -24, 48, -60, 50, -26, 72, -42, 54, -28, 72, -56, 80, -30, 60, -72, 62, -32, 80, -63, 84]