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.

A306513 The number of unordered pairs of coprime integers q and r such that phi(q) + phi(r) = 2n.

Table of values

n a(n)
1 1
2 1
3 5
4 7
5 12
6 10
7 19
8 18
9 20
10 21
11 35
12 32
13 39
14 42
15 38
16 37
17 48
18 46
19 45
20 58
21 64
22 63
23 69
24 73
25 58
26 93
27 71
28 70
29 81
30 92
31 72
32 113
33 96
34 94
35 90
36 100
37 79
38 158
39 120
40 95
41 131
42 153
43 84
44 147
45 129
46 132
47 126
48 150
49 92
50 179
51 157
52 150
53 149
54 187
55 92
56 224
57 177
58 166
59 173
60 207
61 124

List of values

[1, 1, 5, 7, 12, 10, 19, 18, 20, 21, 35, 32, 39, 42, 38, 37, 48, 46, 45, 58, 64, 63, 69, 73, 58, 93, 71, 70, 81, 92, 72, 113, 96, 94, 90, 100, 79, 158, 120, 95, 131, 153, 84, 147, 129, 132, 126, 150, 92, 179, 157, 150, 149, 187, 92, 224, 177, 166, 173, 207, 124]

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

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