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.

A280353 Numbers n such that the sum of the divisors of n divides sum of squares of divisors of n and number of divisors of n divides n.

Table of values

n a(n)
1 1
2 9
3 36
4 180
5 225
6 441
7 450
8 468
9 625
10 1089
11 1476
12 1521
13 1620
14 1800
15 2025
16 2178
17 2340
18 2601
19 3249
20 3600
21 4050
22 4500
23 4761
24 5202
25 5625
26 6561
27 7569
28 8100
29 8649
30 8712
31 9522
32 10000
33 12321
34 13572
35 15129
36 15138
37 16200
38 16641
39 19881
40 20808
41 22500
42 23400
43 25281
44 26244
45 28224
46 28800

List of values

[1, 9, 36, 180, 225, 441, 450, 468, 625, 1089, 1476, 1521, 1620, 1800, 2025, 2178, 2340, 2601, 3249, 3600, 4050, 4500, 4761, 5202, 5625, 6561, 7569, 8100, 8649, 8712, 9522, 10000, 12321, 13572, 15129, 15138, 16200, 16641, 19881, 20808, 22500, 23400, 25281, 26244, 28224, 28800]