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.

A117212 Sum_{d|n} a(d)/d = (-1)^(n-1)/n for n>=1; equals the logarithmic g.f. of A117210.

Table of values

n a(n)
1 1
2 -3
3 -2
4 1
5 -4
6 6
7 -6
8 1
9 -2
10 12
11 -10
12 -2
13 -12
14 18
15 8
16 1
17 -16
18 6
19 -18
20 -4
21 12
22 30
23 -22
24 -2
25 -4
26 36
27 -2
28 -6
29 -28
30 -24
31 -30
32 1
33 20
34 48
35 24
36 -2
37 -36
38 54
39 24
40 -4
41 -40
42 -36
43 -42
44 -10
45 8
46 66
47 -46
48 -2
49 -6
50 12
51 32
52 -12
53 -52
54 6
55 40
56 -6
57 36
58 84
59 -58
60 8
61 -60
62 90
63 12
64 1
65 48
66 -60
67 -66
68 -16
69 44
70 -72
71 -70
72 -2
73 -72
74 108
75 8
76 -18

List of values

[1, -3, -2, 1, -4, 6, -6, 1, -2, 12, -10, -2, -12, 18, 8, 1, -16, 6, -18, -4, 12, 30, -22, -2, -4, 36, -2, -6, -28, -24, -30, 1, 20, 48, 24, -2, -36, 54, 24, -4, -40, -36, -42, -10, 8, 66, -46, -2, -6, 12, 32, -12, -52, 6, 40, -6, 36, 84, -58, 8, -60, 90, 12, 1, 48, -60, -66, -16, 44, -72, -70, -2, -72, 108, 8, -18]