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.

A307777 a(1) = 1; a(n+1) = Sum_{d|n} (-1)^(n/d+d)*a(d).

Table of values

n a(n)
1 1
2 1
3 -2
4 -1
5 1
6 2
7 -2
8 -1
9 0
10 -1
11 -2
12 -1
13 6
14 7
15 -7
16 -7
17 5
18 6
19 -8
20 -7
21 6
22 3
23 -3
24 -2
25 5
26 7
27 -15
28 -16
29 26
30 27
31 -22
32 -21
33 12
34 9
35 -16
36 -16
37 28
38 29
39 -23
40 -18
41 9
42 10
43 -23
44 -22
45 28
46 21
47 -20
48 -19
49 25
50 24
51 -31
52 -27
53 29
54 30
55 -23
56 -23
57 16
58 7
59 -35
60 -34
61 79
62 80
63 -60
64 -57
65 27
66 35
67 -50
68 -49
69 54
70 50
71 -41

List of values

[1, 1, -2, -1, 1, 2, -2, -1, 0, -1, -2, -1, 6, 7, -7, -7, 5, 6, -8, -7, 6, 3, -3, -2, 5, 7, -15, -16, 26, 27, -22, -21, 12, 9, -16, -16, 28, 29, -23, -18, 9, 10, -23, -22, 28, 21, -20, -19, 25, 24, -31, -27, 29, 30, -23, -23, 16, 7, -35, -34, 79, 80, -60, -57, 27, 35, -50, -49, 54, 50, -41]