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.

A250222 a(n) = phi(2n+1) - phi(2n), where phi is A000010.

Table of values

n a(n)
1 1
2 2
3 4
4 2
5 6
6 8
7 2
8 8
9 12
10 4
11 12
12 12
13 6
14 16
15 22
16 4
17 8
18 24
19 6
20 24
21 30
22 4
23 24
24 26
25 12
26 28
27 22
28 12
29 30
30 44
31 6
32 16
33 46
34 12
35 46
36 48
37 4
38 24
39 54
40 22
41 42
42 40
43 14
44 48
45 48
46 16
47 26
48 64
49 18
50 60
51 70
52 0
53 54
54 72
55 32
56 64
57 52
58 16
59 38
60 78
61 20
62 40
63 90
64 20
65 82
66 68
67 6
68 72
69 94
70 44
71 50
72 64

List of values

[1, 2, 4, 2, 6, 8, 2, 8, 12, 4, 12, 12, 6, 16, 22, 4, 8, 24, 6, 24, 30, 4, 24, 26, 12, 28, 22, 12, 30, 44, 6, 16, 46, 12, 46, 48, 4, 24, 54, 22, 42, 40, 14, 48, 48, 16, 26, 64, 18, 60, 70, 0, 54, 72, 32, 64, 52, 16, 38, 78, 20, 40, 90, 20, 82, 68, 6, 72, 94, 44, 50, 64]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.