A003601 - cp's OEIS frontend

A003601 Numbers j such that the average of the divisors of j is an integer: sigma_0(j) divides sigma_1(j). Alternatively, numbers j such that tau(j) (A000005(j)) divides sigma(j) (A000203(j)).

n	a(n)
1	1
2	3
3	5
4	6
5	7
6	11
7	13
8	14
9	15
10	17
11	19
12	20
13	21
14	22
15	23
16	27
17	29
18	30
19	31
20	33
21	35
22	37
23	38
24	39
25	41
26	42
27	43
28	44
29	45
30	46
31	47
32	49
33	51
34	53
35	54
36	55
37	56
38	57
39	59
40	60
41	61
42	62
43	65
44	66
45	67
46	68
47	69
48	70
49	71
50	73
51	77
52	78
53	79
54	83
55	85
56	86
57	87
58	89
59	91
60	92
61	93
62	94
63	95
64	96
65	97
66	99
67	101
68	102
69	103
70	105

[1, 3, 5, 6, 7, 11, 13, 14, 15, 17, 19, 20, 21, 22, 23, 27, 29, 30, 31, 33, 35, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 49, 51, 53, 54, 55, 56, 57, 59, 60, 61, 62, 65, 66, 67, 68, 69, 70, 71, 73, 77, 78, 79, 83, 85, 86, 87, 89, 91, 92, 93, 94, 95, 96, 97, 99, 101, 102, 103, 105]

cp's OEIS Frontend

A003601 Numbers j such that the average of the divisors of j is an integer: sigma_0(j) divides sigma_1(j). Alternatively, numbers j such that tau(j) (A000005(j)) divides sigma(j) (A000203(j)).

Table of values

List of values

n	a(n)
1	1
2	3
3	5
4	6
5	7
6	11
7	13
8	14
9	15
10	17
11	19
12	20
13	21
14	22
15	23
16	27
17	29
18	30
19	31
20	33
21	35
22	37
23	38
24	39
25	41
26	42
27	43
28	44
29	45
30	46
31	47
32	49
33	51
34	53
35	54
36	55
37	56
38	57
39	59
40	60
41	61
42	62
43	65
44	66
45	67
46	68
47	69
48	70
49	71
50	73
51	77
52	78
53	79
54	83
55	85
56	86
57	87
58	89
59	91
60	92
61	93
62	94
63	95
64	96
65	97
66	99
67	101
68	102
69	103
70	105

n	a(n)
1	1
2	3
3	5
4	6
5	7
6	11
7	13
8	14
9	15
10	17
11	19
12	20
13	21
14	22
15	23
16	27
17	29
18	30
19	31
20	33
21	35
22	37
23	38
24	39
25	41
26	42
27	43
28	44
29	45
30	46
31	47
32	49
33	51
34	53
35	54
36	55
37	56
38	57
39	59
40	60
41	61
42	62
43	65
44	66
45	67
46	68
47	69
48	70
49	71
50	73
51	77
52	78
53	79
54	83
55	85
56	86
57	87
58	89
59	91
60	92
61	93
62	94
63	95
64	96
65	97
66	99
67	101
68	102
69	103
70	105

n	a(n)
1	1
2	3
3	5
4	6
5	7
6	11
7	13
8	14
9	15
10	17
11	19
12	20
13	21
14	22
15	23
16	27
17	29
18	30
19	31
20	33
21	35
22	37
23	38
24	39
25	41
26	42
27	43
28	44
29	45
30	46
31	47
32	49
33	51
34	53
35	54
36	55
37	56
38	57
39	59
40	60
41	61
42	62
43	65
44	66
45	67
46	68
47	69
48	70
49	71
50	73
51	77
52	78
53	79
54	83
55	85
56	86
57	87
58	89
59	91
60	92
61	93
62	94
63	95
64	96
65	97
66	99
67	101
68	102
69	103
70	105