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.

A117289 Numbers k for which the cototient k-phi(k) is an enneagonal number (A001106).

Table of values

n a(n)
1 1
2 2
3 3
4 5
5 7
6 11
7 13
8 17
9 19
10 21
11 23
12 27
13 29
14 31
15 36
16 37
17 40
18 41
19 43
20 44
21 46
22 47
23 53
24 59
25 61
26 66
27 67
28 70
29 71
30 73
31 79
32 83
33 89
34 97
35 101
36 103
37 107
38 109
39 113
40 127
41 131
42 137
43 139
44 149
45 151
46 157
47 163
48 167
49 173
50 179
51 181
52 191
53 193
54 197
55 199
56 207
57 211
58 219
59 223
60 227
61 229
62 231

List of values

[1, 2, 3, 5, 7, 11, 13, 17, 19, 21, 23, 27, 29, 31, 36, 37, 40, 41, 43, 44, 46, 47, 53, 59, 61, 66, 67, 70, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 207, 211, 219, 223, 227, 229, 231]

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

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