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.

A351619 a(n) = Sum_{p|n, p prime} (-1)^p.

Table of values

n a(n)
1 0
2 1
3 -1
4 1
5 -1
6 0
7 -1
8 1
9 -1
10 0
11 -1
12 0
13 -1
14 0
15 -2
16 1
17 -1
18 0
19 -1
20 0
21 -2
22 0
23 -1
24 0
25 -1
26 0
27 -1
28 0
29 -1
30 -1
31 -1
32 1
33 -2
34 0
35 -2
36 0
37 -1
38 0
39 -2
40 0
41 -1
42 -1
43 -1
44 0
45 -2
46 0
47 -1
48 0
49 -1
50 0
51 -2
52 0
53 -1
54 0
55 -2
56 0
57 -2
58 0
59 -1
60 -1
61 -1
62 0
63 -2
64 1
65 -2
66 -1
67 -1
68 0
69 -2
70 -1
71 -1
72 0
73 -1
74 0
75 -2
76 0
77 -2
78 -1
79 -1
80 0
81 -1
82 0
83 -1
84 -1
85 -2
86 0
87 -2
88 0
89 -1
90 -1
91 -2
92 0
93 -2
94 0
95 -2
96 0
97 -1
98 0
99 -2
100 0
101 -1

List of values

[0, 1, -1, 1, -1, 0, -1, 1, -1, 0, -1, 0, -1, 0, -2, 1, -1, 0, -1, 0, -2, 0, -1, 0, -1, 0, -1, 0, -1, -1, -1, 1, -2, 0, -2, 0, -1, 0, -2, 0, -1, -1, -1, 0, -2, 0, -1, 0, -1, 0, -2, 0, -1, 0, -2, 0, -2, 0, -1, -1, -1, 0, -2, 1, -2, -1, -1, 0, -2, -1, -1, 0, -1, 0, -2, 0, -2, -1, -1, 0, -1, 0, -1, -1, -2, 0, -2, 0, -1, -1, -2, 0, -2, 0, -2, 0, -1, 0, -2, 0, -1]