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.

A331752 Numbers k such that squarefree part of sigma(k) is equal to squarefree part of 2*k.

Table of values

n a(n)
1 6
2 28
3 468
4 496
5 775
6 2268
7 3780
8 4655
9 7448
10 8128
11 9000
12 10880
13 10976
14 25137
15 40131
16 40176
17 58752
18 62775
19 66960
20 91000
21 137541
22 137940
23 140800
24 160930
25 167400
26 173600
27 195938
28 224450
29 307125
30 377055
31 399360
32 406224
33 417477
34 494832
35 569184
36 603288
37 634725
38 639158
39 658368
40 773175
41 869022
42 881280
43 889056
44 1005480

List of values

[6, 28, 468, 496, 775, 2268, 3780, 4655, 7448, 8128, 9000, 10880, 10976, 25137, 40131, 40176, 58752, 62775, 66960, 91000, 137541, 137940, 140800, 160930, 167400, 173600, 195938, 224450, 307125, 377055, 399360, 406224, 417477, 494832, 569184, 603288, 634725, 639158, 658368, 773175, 869022, 881280, 889056, 1005480]

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

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