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.

A138047 Positive integers n such that (d(n+1) - d(n)) * (-1)^n is nonnegative, where d(n) = the number of positive divisors of n.

Table of values

n a(n)
1 2
2 14
3 21
4 26
5 33
6 34
7 38
8 44
9 45
10 57
11 62
12 74
13 75
14 81
15 85
16 86
17 93
18 94
19 98
20 104
21 105
22 116
23 117
24 118
25 122
26 133
27 134
28 135
29 141
30 142
31 145
32 146
33 147
34 158
35 164
36 165
37 171
38 177
39 188
40 189
41 194
42 201
43 202
44 205
45 206
46 213
47 214
48 217
49 218
50 225
51 230
52 231
53 242
54 243
55 244
56 253

List of values

[2, 14, 21, 26, 33, 34, 38, 44, 45, 57, 62, 74, 75, 81, 85, 86, 93, 94, 98, 104, 105, 116, 117, 118, 122, 133, 134, 135, 141, 142, 145, 146, 147, 158, 164, 165, 171, 177, 188, 189, 194, 201, 202, 205, 206, 213, 214, 217, 218, 225, 230, 231, 242, 243, 244, 253]

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

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