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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.

A117288 Numbers k for which the cototient k-phi(k) is an octagonal number.

Table of values

n a(n)
1 1
2 2
3 3
4 5
5 7
6 11
7 12
8 13
9 14
10 16
11 17
12 19
13 23
14 29
15 31
16 37
17 41
18 43
19 45
20 47
21 53
22 57
23 59
24 61
25 67
26 71
27 73
28 76
29 79
30 83
31 85
32 89
33 97
34 101
35 103
36 107
37 109
38 113
39 127
40 131
41 137
42 139
43 144
44 149
45 151
46 157
47 160
48 163
49 167
50 173
51 176
52 179
53 181
54 184
55 188
56 191
57 193
58 197
59 199
60 211
61 223

List of values

[1, 2, 3, 5, 7, 11, 12, 13, 14, 16, 17, 19, 23, 29, 31, 37, 41, 43, 45, 47, 53, 57, 59, 61, 67, 71, 73, 76, 79, 83, 85, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 144, 149, 151, 157, 160, 163, 167, 173, 176, 179, 181, 184, 188, 191, 193, 197, 199, 211, 223]

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

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