A374379 - cp's OEIS frontend

A374379 a(1) = 1, a(2) = 2. Let i = a(n-2), j = a(n-1), then for n > 2 a(n) is the least novel k such that rad(k) !| rad(ij) whereas rad(ij*k) is a primorial number (A002110), where rad is A007947.

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	6
7	10
8	7
9	9
10	20
11	14
12	12
13	15
14	21
15	8
16	25
17	18
18	28
19	30
20	11
21	35
22	24
23	22
24	70
25	27
26	33
27	140
28	13
29	66
30	105
31	26
32	44
33	210
34	39
35	55
36	42
37	52
38	110
39	63
40	65
41	88
42	84
43	40
44	77
45	36
46	45
47	49
48	16
49	60
50	56
51	99
52	50
53	91
54	132
55	75
56	98
57	121
58	90
59	112
60	143
61	120
62	119
63	286
64	135
65	126
66	154
67	80
68	48
69	147

[1, 2, 3, 5, 4, 6, 10, 7, 9, 20, 14, 12, 15, 21, 8, 25, 18, 28, 30, 11, 35, 24, 22, 70, 27, 33, 140, 13, 66, 105, 26, 44, 210, 39, 55, 42, 52, 110, 63, 65, 88, 84, 40, 77, 36, 45, 49, 16, 60, 56, 99, 50, 91, 132, 75, 98, 121, 90, 112, 143, 120, 119, 286, 135, 126, 154, 80, 48, 147]

cp's OEIS Frontend

A374379 a(1) = 1, a(2) = 2. Let i = a(n-2), j = a(n-1), then for n > 2 a(n) is the least novel k such that rad(k) !| rad(ij) whereas rad(ij*k) is a primorial number (A002110), where rad is A007947.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	6
7	10
8	7
9	9
10	20
11	14
12	12
13	15
14	21
15	8
16	25
17	18
18	28
19	30
20	11
21	35
22	24
23	22
24	70
25	27
26	33
27	140
28	13
29	66
30	105
31	26
32	44
33	210
34	39
35	55
36	42
37	52
38	110
39	63
40	65
41	88
42	84
43	40
44	77
45	36
46	45
47	49
48	16
49	60
50	56
51	99
52	50
53	91
54	132
55	75
56	98
57	121
58	90
59	112
60	143
61	120
62	119
63	286
64	135
65	126
66	154
67	80
68	48
69	147

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	6
7	10
8	7
9	9
10	20
11	14
12	12
13	15
14	21
15	8
16	25
17	18
18	28
19	30
20	11
21	35
22	24
23	22
24	70
25	27
26	33
27	140
28	13
29	66
30	105
31	26
32	44
33	210
34	39
35	55
36	42
37	52
38	110
39	63
40	65
41	88
42	84
43	40
44	77
45	36
46	45
47	49
48	16
49	60
50	56
51	99
52	50
53	91
54	132
55	75
56	98
57	121
58	90
59	112
60	143
61	120
62	119
63	286
64	135
65	126
66	154
67	80
68	48
69	147

cp's OEIS Frontend

A374379 a(1) = 1, a(2) = 2. Let i = a(n-2), j = a(n-1), then for n > 2 a(n) is the least novel k such that rad(k) !| rad(i*j) whereas rad(i*j*k) is a primorial number (A002110), where rad is A007947.

Table of values

List of values

A374379 a(1) = 1, a(2) = 2. Let i = a(n-2), j = a(n-1), then for n > 2 a(n) is the least novel k such that rad(k) !| rad(ij) whereas rad(ij*k) is a primorial number (A002110), where rad is A007947.

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	6
7	10
8	7
9	9
10	20
11	14
12	12
13	15
14	21
15	8
16	25
17	18
18	28
19	30
20	11
21	35
22	24
23	22
24	70
25	27
26	33
27	140
28	13
29	66
30	105
31	26
32	44
33	210
34	39
35	55
36	42
37	52
38	110
39	63
40	65
41	88
42	84
43	40
44	77
45	36
46	45
47	49
48	16
49	60
50	56
51	99
52	50
53	91
54	132
55	75
56	98
57	121
58	90
59	112
60	143
61	120
62	119
63	286
64	135
65	126
66	154
67	80
68	48
69	147