A222208 - cp's OEIS frontend

A222208 a(1) = 1, a(2) = 3; for n>2, a(n) = smallest number not in {a(1), ..., a(n-1)} such that a(n) is divisible by a(d) for all divisors d of n.

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	5
8	18
9	8
10	24
11	7
12	36
13	9
14	15
15	16
16	54
17	10
18	48
19	11
20	72
21	20
22	21
23	13
24	108
25	28
26	27
27	32
28	30
29	14
30	96
31	17
32	162
33	42
34	60
35	40
36	144
37	19
38	33
39	90
40	216
41	22
42	120
43	23
44	84
45	64
46	39
47	25
48	324
49	35
50	168
51	50
52	270
53	26
54	192
55	56
56	180
57	44
58	126
59	29
60	288
61	31
62	51
63	80
64	486

[1, 3, 2, 6, 4, 12, 5, 18, 8, 24, 7, 36, 9, 15, 16, 54, 10, 48, 11, 72, 20, 21, 13, 108, 28, 27, 32, 30, 14, 96, 17, 162, 42, 60, 40, 144, 19, 33, 90, 216, 22, 120, 23, 84, 64, 39, 25, 324, 35, 168, 50, 270, 26, 192, 56, 180, 44, 126, 29, 288, 31, 51, 80, 486]

cp's OEIS Frontend

A222208 a(1) = 1, a(2) = 3; for n>2, a(n) = smallest number not in {a(1), ..., a(n-1)} such that a(n) is divisible by a(d) for all divisors d of n.

Table of values

List of values

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	5
8	18
9	8
10	24
11	7
12	36
13	9
14	15
15	16
16	54
17	10
18	48
19	11
20	72
21	20
22	21
23	13
24	108
25	28
26	27
27	32
28	30
29	14
30	96
31	17
32	162
33	42
34	60
35	40
36	144
37	19
38	33
39	90
40	216
41	22
42	120
43	23
44	84
45	64
46	39
47	25
48	324
49	35
50	168
51	50
52	270
53	26
54	192
55	56
56	180
57	44
58	126
59	29
60	288
61	31
62	51
63	80
64	486

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	5
8	18
9	8
10	24
11	7
12	36
13	9
14	15
15	16
16	54
17	10
18	48
19	11
20	72
21	20
22	21
23	13
24	108
25	28
26	27
27	32
28	30
29	14
30	96
31	17
32	162
33	42
34	60
35	40
36	144
37	19
38	33
39	90
40	216
41	22
42	120
43	23
44	84
45	64
46	39
47	25
48	324
49	35
50	168
51	50
52	270
53	26
54	192
55	56
56	180
57	44
58	126
59	29
60	288
61	31
62	51
63	80
64	486

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	5
8	18
9	8
10	24
11	7
12	36
13	9
14	15
15	16
16	54
17	10
18	48
19	11
20	72
21	20
22	21
23	13
24	108
25	28
26	27
27	32
28	30
29	14
30	96
31	17
32	162
33	42
34	60
35	40
36	144
37	19
38	33
39	90
40	216
41	22
42	120
43	23
44	84
45	64
46	39
47	25
48	324
49	35
50	168
51	50
52	270
53	26
54	192
55	56
56	180
57	44
58	126
59	29
60	288
61	31
62	51
63	80
64	486