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.

A065655 Composite numbers k such that sigma(k)*(phi(k) + 2) is a square.

Table of values

n a(n)
1 28
2 90
3 156
4 184
5 374
6 1855
7 2162
8 2170
9 2280
10 2376
11 2415
12 2665
13 3160
14 4970
15 5270
16 5740
17 6402
18 6494
19 7414
20 8400
21 9118
22 10656
23 11155
24 12400
25 14632
26 14910
27 15010
28 15906
29 18183
30 18792
31 22648
32 24645
33 24734
34 24920
35 25844
36 26670
37 27478
38 28990

List of values

[28, 90, 156, 184, 374, 1855, 2162, 2170, 2280, 2376, 2415, 2665, 3160, 4970, 5270, 5740, 6402, 6494, 7414, 8400, 9118, 10656, 11155, 12400, 14632, 14910, 15010, 15906, 18183, 18792, 22648, 24645, 24734, 24920, 25844, 26670, 27478, 28990]

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

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