A020487 - cp's OEIS frontend

A020487 Antiharmonic numbers: numbers k such that sigma_1(k) divides sigma_2(k).

n	a(n)
1	1
2	4
3	9
4	16
5	20
6	25
7	36
8	49
9	50
10	64
11	81
12	100
13	117
14	121
15	144
16	169
17	180
18	196
19	200
20	225
21	242
22	256
23	289
24	324
25	325
26	361
27	400
28	441
29	450
30	468
31	484
32	500
33	529
34	576
35	578
36	605
37	625
38	650
39	676
40	729
41	784
42	800
43	841
44	900
45	961
46	968
47	980
48	1024
49	1025
50	1058
51	1089
52	1156
53	1225
54	1280
55	1296

[1, 4, 9, 16, 20, 25, 36, 49, 50, 64, 81, 100, 117, 121, 144, 169, 180, 196, 200, 225, 242, 256, 289, 324, 325, 361, 400, 441, 450, 468, 484, 500, 529, 576, 578, 605, 625, 650, 676, 729, 784, 800, 841, 900, 961, 968, 980, 1024, 1025, 1058, 1089, 1156, 1225, 1280, 1296]

cp's OEIS Frontend

A020487 Antiharmonic numbers: numbers k such that sigma_1(k) divides sigma_2(k).

Table of values

List of values