A143869 - cp's OEIS frontend

A143869 An integer k is called regular (mod n) if there is an integer x such that k^2 x == k (mod n). Then these numbers are the sum of regular integers k (mod n) such that 1 <= k <= n for n=1,2,... .

n	a(n)
1	1
2	3
3	6
4	8
5	15
6	21
7	28
8	24
9	36
10	55
11	66
12	60
13	91
14	105
15	120
16	80
17	153
18	135
19	190
20	160
21	231
22	253
23	276
24	192
25	275
26	351
27	270
28	308
29	435
30	465
31	496
32	288
33	561
34	595
35	630
36	396
37	703
38	741
39	780
40	520
41	861
42	903
43	946
44	748
45	810
46	1081
47	1128
48	672
49	1078
50	1075
51	1326
52	1040
53	1431
54	1053

[1, 3, 6, 8, 15, 21, 28, 24, 36, 55, 66, 60, 91, 105, 120, 80, 153, 135, 190, 160, 231, 253, 276, 192, 275, 351, 270, 308, 435, 465, 496, 288, 561, 595, 630, 396, 703, 741, 780, 520, 861, 903, 946, 748, 810, 1081, 1128, 672, 1078, 1075, 1326, 1040, 1431, 1053]

cp's OEIS Frontend

A143869 An integer k is called regular (mod n) if there is an integer x such that k^2 x == k (mod n). Then these numbers are the sum of regular integers k (mod n) such that 1 <= k <= n for n=1,2,... .

Table of values

List of values