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.

A140128 A positive integer k is included if d(d(k)) = d(d(k+1)), where d(k) is the number of divisors of k.

Table of values

n a(n)
1 2
2 3
3 4
4 14
5 16
6 21
7 26
8 33
9 34
10 35
11 38
12 44
13 57
14 75
15 85
16 86
17 93
18 94
19 98
20 104
21 116
22 118
23 122
24 133
25 135
26 141
27 142
28 145
29 147
30 152
31 153
32 158
33 164
34 170
35 171
36 174
37 175
38 177
39 188
40 189
41 201
42 202
43 205
44 207
45 213
46 214
47 217
48 218
49 225
50 230
51 231
52 242
53 243
54 244
55 245
56 253
57 272

List of values

[2, 3, 4, 14, 16, 21, 26, 33, 34, 35, 38, 44, 57, 75, 85, 86, 93, 94, 98, 104, 116, 118, 122, 133, 135, 141, 142, 145, 147, 152, 153, 158, 164, 170, 171, 174, 175, 177, 188, 189, 201, 202, 205, 207, 213, 214, 217, 218, 225, 230, 231, 242, 243, 244, 245, 253, 272]

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

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