A357942 - cp's OEIS frontend

A357942 a(1)=1, a(2)=2. Thereafter, if there are prime divisors p | a(n-1) that are coprime to a(n-2), a(n) is the least novel multiple of the product of these primes. Otherwise a(n) is the least novel multiple of the squarefree kernel of a(n-1). See comments.

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	9
7	12
8	8
9	10
10	5
11	15
12	18
13	14
14	7
15	21
16	24
17	16
18	20
19	25
20	30
21	36
22	42
23	28
24	56
25	70
26	35
27	105
28	27
29	33
30	11
31	22
32	26
33	13
34	39
35	45
36	40
37	32
38	34
39	17
40	51
41	48
42	38
43	19
44	57
45	54
46	44
47	55
48	50
49	46
50	23
51	69
52	60
53	80
54	90
55	63
56	49
57	77
58	66
59	72
60	78
61	52
62	104
63	130
64	65
65	195
66	75
67	120

[1, 2, 4, 6, 3, 9, 12, 8, 10, 5, 15, 18, 14, 7, 21, 24, 16, 20, 25, 30, 36, 42, 28, 56, 70, 35, 105, 27, 33, 11, 22, 26, 13, 39, 45, 40, 32, 34, 17, 51, 48, 38, 19, 57, 54, 44, 55, 50, 46, 23, 69, 60, 80, 90, 63, 49, 77, 66, 72, 78, 52, 104, 130, 65, 195, 75, 120]

cp's OEIS Frontend

A357942 a(1)=1, a(2)=2. Thereafter, if there are prime divisors p | a(n-1) that are coprime to a(n-2), a(n) is the least novel multiple of the product of these primes. Otherwise a(n) is the least novel multiple of the squarefree kernel of a(n-1). See comments.

Table of values

List of values

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	9
7	12
8	8
9	10
10	5
11	15
12	18
13	14
14	7
15	21
16	24
17	16
18	20
19	25
20	30
21	36
22	42
23	28
24	56
25	70
26	35
27	105
28	27
29	33
30	11
31	22
32	26
33	13
34	39
35	45
36	40
37	32
38	34
39	17
40	51
41	48
42	38
43	19
44	57
45	54
46	44
47	55
48	50
49	46
50	23
51	69
52	60
53	80
54	90
55	63
56	49
57	77
58	66
59	72
60	78
61	52
62	104
63	130
64	65
65	195
66	75
67	120

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	9
7	12
8	8
9	10
10	5
11	15
12	18
13	14
14	7
15	21
16	24
17	16
18	20
19	25
20	30
21	36
22	42
23	28
24	56
25	70
26	35
27	105
28	27
29	33
30	11
31	22
32	26
33	13
34	39
35	45
36	40
37	32
38	34
39	17
40	51
41	48
42	38
43	19
44	57
45	54
46	44
47	55
48	50
49	46
50	23
51	69
52	60
53	80
54	90
55	63
56	49
57	77
58	66
59	72
60	78
61	52
62	104
63	130
64	65
65	195
66	75
67	120

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	9
7	12
8	8
9	10
10	5
11	15
12	18
13	14
14	7
15	21
16	24
17	16
18	20
19	25
20	30
21	36
22	42
23	28
24	56
25	70
26	35
27	105
28	27
29	33
30	11
31	22
32	26
33	13
34	39
35	45
36	40
37	32
38	34
39	17
40	51
41	48
42	38
43	19
44	57
45	54
46	44
47	55
48	50
49	46
50	23
51	69
52	60
53	80
54	90
55	63
56	49
57	77
58	66
59	72
60	78
61	52
62	104
63	130
64	65
65	195
66	75
67	120