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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.

A097982 Numbers n such that (phi(n) + sigma(n))/(rad(n))^2 is an integer > 1 (phi=A000010, sigma=A000203, rad=A007947).

Table of values

n a(n)
1 1
2 864
3 2430
4 7776
5 27000
6 55296
7 69984
8 82134
9 215622
10 432000
11 497664
12 629856
13 675000
14 862488
15 1499136
16 1749600
17 2187000
18 2667168
19 3449952
20 3538944
21 4287500
22 4312440
23 4478976
24 4563000
25 5668704
26 6912000
27 10800000
28 13045131
29 13799808
30 16875000
31 18670176
32 19773000

List of values

[1, 864, 2430, 7776, 27000, 55296, 69984, 82134, 215622, 432000, 497664, 629856, 675000, 862488, 1499136, 1749600, 2187000, 2667168, 3449952, 3538944, 4287500, 4312440, 4478976, 4563000, 5668704, 6912000, 10800000, 13045131, 13799808, 16875000, 18670176, 19773000]

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

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