A350767 - cp's OEIS frontend

A350767 a(1)=1. Thereafter, a(n+1) is the least unused number k such that either d(j(n)) properly divides d(k) or d(k) properly divides d(j(n)), where j(n) = a(n)+1 and d is the divisor counting function A000005.

n	a(n)
1	1
2	6
3	8
4	12
5	10
6	14
7	2
8	15
9	48
10	18
11	20
12	3
13	28
14	21
15	5
16	7
17	11
18	4
19	22
20	24
21	32
22	13
23	17
24	9
25	19
26	23
27	26
28	29
29	27
30	25
31	30
32	33
33	31
34	37
35	40
36	34
37	41
38	35
39	49
40	43
41	47
42	16
43	38
44	42
45	39
46	46
47	44
48	53
49	51
50	59
51	45
52	54
53	56
54	60
55	50
56	61
57	66
58	52
59	55
60	57
61	67
62	71
63	58
64	62
65	72
66	63
67	192
68	65

[1, 6, 8, 12, 10, 14, 2, 15, 48, 18, 20, 3, 28, 21, 5, 7, 11, 4, 22, 24, 32, 13, 17, 9, 19, 23, 26, 29, 27, 25, 30, 33, 31, 37, 40, 34, 41, 35, 49, 43, 47, 16, 38, 42, 39, 46, 44, 53, 51, 59, 45, 54, 56, 60, 50, 61, 66, 52, 55, 57, 67, 71, 58, 62, 72, 63, 192, 65]

cp's OEIS Frontend

A350767 a(1)=1. Thereafter, a(n+1) is the least unused number k such that either d(j(n)) properly divides d(k) or d(k) properly divides d(j(n)), where j(n) = a(n)+1 and d is the divisor counting function A000005.

Table of values

List of values

n	a(n)
1	1
2	6
3	8
4	12
5	10
6	14
7	2
8	15
9	48
10	18
11	20
12	3
13	28
14	21
15	5
16	7
17	11
18	4
19	22
20	24
21	32
22	13
23	17
24	9
25	19
26	23
27	26
28	29
29	27
30	25
31	30
32	33
33	31
34	37
35	40
36	34
37	41
38	35
39	49
40	43
41	47
42	16
43	38
44	42
45	39
46	46
47	44
48	53
49	51
50	59
51	45
52	54
53	56
54	60
55	50
56	61
57	66
58	52
59	55
60	57
61	67
62	71
63	58
64	62
65	72
66	63
67	192
68	65

n	a(n)
1	1
2	6
3	8
4	12
5	10
6	14
7	2
8	15
9	48
10	18
11	20
12	3
13	28
14	21
15	5
16	7
17	11
18	4
19	22
20	24
21	32
22	13
23	17
24	9
25	19
26	23
27	26
28	29
29	27
30	25
31	30
32	33
33	31
34	37
35	40
36	34
37	41
38	35
39	49
40	43
41	47
42	16
43	38
44	42
45	39
46	46
47	44
48	53
49	51
50	59
51	45
52	54
53	56
54	60
55	50
56	61
57	66
58	52
59	55
60	57
61	67
62	71
63	58
64	62
65	72
66	63
67	192
68	65

n	a(n)
1	1
2	6
3	8
4	12
5	10
6	14
7	2
8	15
9	48
10	18
11	20
12	3
13	28
14	21
15	5
16	7
17	11
18	4
19	22
20	24
21	32
22	13
23	17
24	9
25	19
26	23
27	26
28	29
29	27
30	25
31	30
32	33
33	31
34	37
35	40
36	34
37	41
38	35
39	49
40	43
41	47
42	16
43	38
44	42
45	39
46	46
47	44
48	53
49	51
50	59
51	45
52	54
53	56
54	60
55	50
56	61
57	66
58	52
59	55
60	57
61	67
62	71
63	58
64	62
65	72
66	63
67	192
68	65