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.

A145378 a(n) = Sum_{d|n} sigma(d) - 2*Sum_{2c|n} sigma(c) + 4*Sum_{4b|n} sigma(b).

Table of values

n a(n)
1 1
2 2
3 5
4 7
5 7
6 10
7 9
8 20
9 18
10 14
11 13
12 35
13 15
14 18
15 35
16 49
17 19
18 36
19 21
20 49
21 45
22 26
23 25
24 100
25 38
26 30
27 58
28 63
29 31
30 70
31 33
32 110
33 65
34 38
35 63
36 126
37 39
38 42
39 75
40 140
41 43
42 90
43 45
44 91
45 126
46 50
47 49
48 245
49 66
50 76
51 95
52 105
53 55
54 116
55 91
56 180
57 105
58 62
59 61
60 245
61 63
62 66
63 162
64 235
65 105
66 130
67 69

List of values

[1, 2, 5, 7, 7, 10, 9, 20, 18, 14, 13, 35, 15, 18, 35, 49, 19, 36, 21, 49, 45, 26, 25, 100, 38, 30, 58, 63, 31, 70, 33, 110, 65, 38, 63, 126, 39, 42, 75, 140, 43, 90, 45, 91, 126, 50, 49, 245, 66, 76, 95, 105, 55, 116, 91, 180, 105, 62, 61, 245, 63, 66, 162, 235, 105, 130, 69]