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.

A073858 Numbers k such that sigma(phi(k)) divides phi(sigma(k)).

Table of values

n a(n)
1 1
2 2
3 4
4 9
5 16
6 18
7 64
8 100
9 225
10 242
11 450
12 516
13 729
14 1458
15 3872
16 4096
17 4624
18 13932
19 14406
20 17672
21 18225
22 20124
23 21780
24 28900
25 29262
26 29616
27 36450
28 45996
29 62500
30 65025
31 65536
32 76832
33 92778
34 95916
35 106092
36 106308
37 114630
38 114930

List of values

[1, 2, 4, 9, 16, 18, 64, 100, 225, 242, 450, 516, 729, 1458, 3872, 4096, 4624, 13932, 14406, 17672, 18225, 20124, 21780, 28900, 29262, 29616, 36450, 45996, 62500, 65025, 65536, 76832, 92778, 95916, 106092, 106308, 114630, 114930]

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

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