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.

A115165 Odd numbers k such that k-1 and k+1 have the same number of distinct prime divisors.

Table of values

n a(n)
1 3
2 11
3 13
4 19
5 21
6 23
7 25
8 27
9 35
10 37
11 39
12 45
13 47
14 49
15 51
16 53
17 55
18 57
19 73
20 75
21 81
22 87
23 93
24 95
25 97
26 99
27 105
28 107
29 117
30 123
31 131
32 135
33 139
34 143
35 145
36 147
37 155
38 159
39 161
40 163
41 165
42 169
43 177
44 181
45 193
46 195
47 201
48 207
49 213
50 215
51 217
52 221
53 225
54 229
55 239
56 243
57 249
58 259
59 265

List of values

[3, 11, 13, 19, 21, 23, 25, 27, 35, 37, 39, 45, 47, 49, 51, 53, 55, 57, 73, 75, 81, 87, 93, 95, 97, 99, 105, 107, 117, 123, 131, 135, 139, 143, 145, 147, 155, 159, 161, 163, 165, 169, 177, 181, 193, 195, 201, 207, 213, 215, 217, 221, 225, 229, 239, 243, 249, 259, 265]

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

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