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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.

A291549 Numbers n such that both phi(n) and psi(n) are perfect squares.

Table of values

n a(n)
1 1
2 60
3 170
4 240
5 315
6 540
7 679
8 680
9 960
10 1500
11 2142
12 2160
13 2720
14 2835
15 3840
16 4250
17 4365
18 4860
19 5770
20 6000
21 7875
22 8568
23 8640
24 9154
25 9809
26 10880
27 13500
28 14322
29 15360
30 15435
31 17000
32 19278
33 19440
34 22413
35 23080
36 24000
37 25515
38 29682
39 33271
40 34272
41 34560
42 36616
43 37114
44 37500

List of values

[1, 60, 170, 240, 315, 540, 679, 680, 960, 1500, 2142, 2160, 2720, 2835, 3840, 4250, 4365, 4860, 5770, 6000, 7875, 8568, 8640, 9154, 9809, 10880, 13500, 14322, 15360, 15435, 17000, 19278, 19440, 22413, 23080, 24000, 25515, 29682, 33271, 34272, 34560, 36616, 37114, 37500]

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

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