A066764 - cp's OEIS frontend

A066764 Numbers k such that (k, sigma(k)) lies on a circle with integral radius centered at the origin, i.e., k^2 + sigma(k)^2 is a square.

n	a(n)
1	3
2	8
3	30
4	140
5	315
6	319
7	460
8	840
9	864
10	936
11	1040
12	1287
13	1836
14	2480
15	2600
16	6076
17	6200
18	7788
19	11398
20	12035
21	12415
22	12584
23	13260
24	13734
25	15886
26	18480
27	26078
28	33820
29	40640
30	42665
31	46200
32	55860
33	68352
34	70266
35	70645
36	75330
37	78939
38	81740
39	98230

[3, 8, 30, 140, 315, 319, 460, 840, 864, 936, 1040, 1287, 1836, 2480, 2600, 6076, 6200, 7788, 11398, 12035, 12415, 12584, 13260, 13734, 15886, 18480, 26078, 33820, 40640, 42665, 46200, 55860, 68352, 70266, 70645, 75330, 78939, 81740, 98230]

cp's OEIS Frontend

A066764 Numbers k such that (k, sigma(k)) lies on a circle with integral radius centered at the origin, i.e., k^2 + sigma(k)^2 is a square.

Table of values

List of values