A384308 - cp's OEIS frontend

A384308 a(1) = 3; for n > 1, a(n) is the smallest number that has not appeared before and has the same set of prime divisors as a(n-1) + 1.

n	a(n)
1	3
2	2
3	9
4	10
5	11
6	6
7	7
8	4
9	5
10	12
11	13
12	14
13	15
14	8
15	27
16	28
17	29
18	30
19	31
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	24
29	25
30	26
31	81
32	82
33	83
34	42
35	43
36	44
37	45
38	46
39	47
40	36
41	37
42	38
43	39
44	40
45	41
46	84
47	85
48	86
49	87
50	88
51	89
52	60
53	61
54	62
55	63
56	32
57	33
58	34
59	35
60	48
61	49
62	50
63	51
64	52
65	53
66	54
67	55
68	56
69	57
70	58
71	59
72	90
73	91
74	92
75	93
76	94
77	95
78	72
79	73
80	74
81	75

[3, 2, 9, 10, 11, 6, 7, 4, 5, 12, 13, 14, 15, 8, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 81, 82, 83, 42, 43, 44, 45, 46, 47, 36, 37, 38, 39, 40, 41, 84, 85, 86, 87, 88, 89, 60, 61, 62, 63, 32, 33, 34, 35, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 90, 91, 92, 93, 94, 95, 72, 73, 74, 75]

cp's OEIS Frontend

A384308 a(1) = 3; for n > 1, a(n) is the smallest number that has not appeared before and has the same set of prime divisors as a(n-1) + 1.

Table of values

List of values

n	a(n)
1	3
2	2
3	9
4	10
5	11
6	6
7	7
8	4
9	5
10	12
11	13
12	14
13	15
14	8
15	27
16	28
17	29
18	30
19	31
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	24
29	25
30	26
31	81
32	82
33	83
34	42
35	43
36	44
37	45
38	46
39	47
40	36
41	37
42	38
43	39
44	40
45	41
46	84
47	85
48	86
49	87
50	88
51	89
52	60
53	61
54	62
55	63
56	32
57	33
58	34
59	35
60	48
61	49
62	50
63	51
64	52
65	53
66	54
67	55
68	56
69	57
70	58
71	59
72	90
73	91
74	92
75	93
76	94
77	95
78	72
79	73
80	74
81	75

n	a(n)
1	3
2	2
3	9
4	10
5	11
6	6
7	7
8	4
9	5
10	12
11	13
12	14
13	15
14	8
15	27
16	28
17	29
18	30
19	31
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	24
29	25
30	26
31	81
32	82
33	83
34	42
35	43
36	44
37	45
38	46
39	47
40	36
41	37
42	38
43	39
44	40
45	41
46	84
47	85
48	86
49	87
50	88
51	89
52	60
53	61
54	62
55	63
56	32
57	33
58	34
59	35
60	48
61	49
62	50
63	51
64	52
65	53
66	54
67	55
68	56
69	57
70	58
71	59
72	90
73	91
74	92
75	93
76	94
77	95
78	72
79	73
80	74
81	75

n	a(n)
1	3
2	2
3	9
4	10
5	11
6	6
7	7
8	4
9	5
10	12
11	13
12	14
13	15
14	8
15	27
16	28
17	29
18	30
19	31
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	24
29	25
30	26
31	81
32	82
33	83
34	42
35	43
36	44
37	45
38	46
39	47
40	36
41	37
42	38
43	39
44	40
45	41
46	84
47	85
48	86
49	87
50	88
51	89
52	60
53	61
54	62
55	63
56	32
57	33
58	34
59	35
60	48
61	49
62	50
63	51
64	52
65	53
66	54
67	55
68	56
69	57
70	58
71	59
72	90
73	91
74	92
75	93
76	94
77	95
78	72
79	73
80	74
81	75