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.

A033632 Numbers k such that sigma(phi(k)) = phi(sigma(k)).

Table of values

n a(n)
1 1
2 9
3 225
4 242
5 516
6 729
7 3872
8 13932
9 14406
10 17672
11 18225
12 20124
13 21780
14 29262
15 29616
16 45996
17 65025
18 76832
19 92778
20 95916
21 106092
22 106308
23 114630
24 114930
25 121872
26 125652
27 140130
28 140625
29 145794
30 149124
31 160986
32 179562
33 185100
34 234876
35 248652
36 252978
37 256860

List of values

[1, 9, 225, 242, 516, 729, 3872, 13932, 14406, 17672, 18225, 20124, 21780, 29262, 29616, 45996, 65025, 76832, 92778, 95916, 106092, 106308, 114630, 114930, 121872, 125652, 140130, 140625, 145794, 149124, 160986, 179562, 185100, 234876, 248652, 252978, 256860]

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

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