A324243 - cp's OEIS frontend

A324243 Rotkiewicz numbers: numbers k such that a^sigma(k) == b^sigma(k) (mod k) for all pairs of numbers a, b such that gcd(a*b, k) = 1, where sigma(k) is the sum of divisors of k (A000203).

n	a(n)
1	1
2	2
3	3
4	6
5	12
6	14
7	15
8	24
9	30
10	35
11	42
12	48
13	56
14	60
15	65
16	70
17	78
18	88
19	105
20	119
21	120
22	126
23	130
24	140
25	168
26	182
27	190
28	195
29	210
30	224
31	238
32	240
33	248
34	255
35	260
36	264
37	270
38	280
39	312
40	315
41	348
42	357
43	370
44	377
45	390
46	418
47	420
48	440
49	455
50	459
51	476
52	480
53	504
54	510
55	520
56	546
57	560

[1, 2, 3, 6, 12, 14, 15, 24, 30, 35, 42, 48, 56, 60, 65, 70, 78, 88, 105, 119, 120, 126, 130, 140, 168, 182, 190, 195, 210, 224, 238, 240, 248, 255, 260, 264, 270, 280, 312, 315, 348, 357, 370, 377, 390, 418, 420, 440, 455, 459, 476, 480, 504, 510, 520, 546, 560]

cp's OEIS Frontend

A324243 Rotkiewicz numbers: numbers k such that a^sigma(k) == b^sigma(k) (mod k) for all pairs of numbers a, b such that gcd(a*b, k) = 1, where sigma(k) is the sum of divisors of k (A000203).

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	6
5	12
6	14
7	15
8	24
9	30
10	35
11	42
12	48
13	56
14	60
15	65
16	70
17	78
18	88
19	105
20	119
21	120
22	126
23	130
24	140
25	168
26	182
27	190
28	195
29	210
30	224
31	238
32	240
33	248
34	255
35	260
36	264
37	270
38	280
39	312
40	315
41	348
42	357
43	370
44	377
45	390
46	418
47	420
48	440
49	455
50	459
51	476
52	480
53	504
54	510
55	520
56	546
57	560

n	a(n)
1	1
2	2
3	3
4	6
5	12
6	14
7	15
8	24
9	30
10	35
11	42
12	48
13	56
14	60
15	65
16	70
17	78
18	88
19	105
20	119
21	120
22	126
23	130
24	140
25	168
26	182
27	190
28	195
29	210
30	224
31	238
32	240
33	248
34	255
35	260
36	264
37	270
38	280
39	312
40	315
41	348
42	357
43	370
44	377
45	390
46	418
47	420
48	440
49	455
50	459
51	476
52	480
53	504
54	510
55	520
56	546
57	560

n	a(n)
1	1
2	2
3	3
4	6
5	12
6	14
7	15
8	24
9	30
10	35
11	42
12	48
13	56
14	60
15	65
16	70
17	78
18	88
19	105
20	119
21	120
22	126
23	130
24	140
25	168
26	182
27	190
28	195
29	210
30	224
31	238
32	240
33	248
34	255
35	260
36	264
37	270
38	280
39	312
40	315
41	348
42	357
43	370
44	377
45	390
46	418
47	420
48	440
49	455
50	459
51	476
52	480
53	504
54	510
55	520
56	546
57	560