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.

A212921 Composite number n = Product(p_j^k_j) that under the iteration of the map Product (p_j^k_j) -> Sum (p_j * k_j) reaches a limit that divides the number itself.

Table of values

n a(n)
1 4
2 15
3 20
4 21
5 35
6 42
7 55
8 65
9 70
10 95
11 100
12 105
13 110
14 120
15 125
16 130
17 135
18 140
19 150
20 160
21 161
22 170
23 180
24 182
25 187
26 190
27 200
28 203
29 217
30 220
31 225
32 231
33 240
34 260
35 270
36 280
37 285
38 301
39 305
40 312
41 315
42 319
43 322
44 340
45 343
46 351
47 365
48 370
49 371
50 375
51 395
52 400
53 406
54 407

List of values

[4, 15, 20, 21, 35, 42, 55, 65, 70, 95, 100, 105, 110, 120, 125, 130, 135, 140, 150, 160, 161, 170, 180, 182, 187, 190, 200, 203, 217, 220, 225, 231, 240, 260, 270, 280, 285, 301, 305, 312, 315, 319, 322, 340, 343, 351, 365, 370, 371, 375, 395, 400, 406, 407]

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

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