A359804 - cp's OEIS frontend

A359804 a(1) = 1, a(2) = 2; thereafter let p be the smallest prime that does not divide a(n-2)*a(n-1), then a(n) is the smallest multiple of p that is not yet in the sequence.

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	6
7	10
8	7
9	9
10	8
11	15
12	14
13	11
14	12
15	20
16	21
17	22
18	25
19	18
20	28
21	30
22	33
23	35
24	16
25	24
26	40
27	42
28	44
29	45
30	49
31	26
32	27
33	50
34	56
35	36
36	55
37	63
38	32
39	60
40	70
41	66
42	13
43	65
44	34
45	39
46	75
47	38
48	77
49	48
50	80
51	84
52	88
53	85
54	51
55	46
56	90
57	91
58	99
59	52
60	95
61	54
62	98
63	100
64	57
65	105
66	58
67	110
68	69
69	112
70	115
71	72
72	119
73	120
74	121

[1, 2, 3, 5, 4, 6, 10, 7, 9, 8, 15, 14, 11, 12, 20, 21, 22, 25, 18, 28, 30, 33, 35, 16, 24, 40, 42, 44, 45, 49, 26, 27, 50, 56, 36, 55, 63, 32, 60, 70, 66, 13, 65, 34, 39, 75, 38, 77, 48, 80, 84, 88, 85, 51, 46, 90, 91, 99, 52, 95, 54, 98, 100, 57, 105, 58, 110, 69, 112, 115, 72, 119, 120, 121]

cp's OEIS Frontend

A359804 a(1) = 1, a(2) = 2; thereafter let p be the smallest prime that does not divide a(n-2)*a(n-1), then a(n) is the smallest multiple of p that is not yet in the sequence.

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	8
11	15
12	14
13	11
14	12
15	20
16	21
17	22
18	25
19	18
20	28
21	30
22	33
23	35
24	16
25	24
26	40
27	42
28	44
29	45
30	49
31	26
32	27
33	50
34	56
35	36
36	55
37	63
38	32
39	60
40	70
41	66
42	13
43	65
44	34
45	39
46	75
47	38
48	77
49	48
50	80
51	84
52	88
53	85
54	51
55	46
56	90
57	91
58	99
59	52
60	95
61	54
62	98
63	100
64	57
65	105
66	58
67	110
68	69
69	112
70	115
71	72
72	119
73	120
74	121

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	6
7	10
8	7
9	9
10	8
11	15
12	14
13	11
14	12
15	20
16	21
17	22
18	25
19	18
20	28
21	30
22	33
23	35
24	16
25	24
26	40
27	42
28	44
29	45
30	49
31	26
32	27
33	50
34	56
35	36
36	55
37	63
38	32
39	60
40	70
41	66
42	13
43	65
44	34
45	39
46	75
47	38
48	77
49	48
50	80
51	84
52	88
53	85
54	51
55	46
56	90
57	91
58	99
59	52
60	95
61	54
62	98
63	100
64	57
65	105
66	58
67	110
68	69
69	112
70	115
71	72
72	119
73	120
74	121

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	6
7	10
8	7
9	9
10	8
11	15
12	14
13	11
14	12
15	20
16	21
17	22
18	25
19	18
20	28
21	30
22	33
23	35
24	16
25	24
26	40
27	42
28	44
29	45
30	49
31	26
32	27
33	50
34	56
35	36
36	55
37	63
38	32
39	60
40	70
41	66
42	13
43	65
44	34
45	39
46	75
47	38
48	77
49	48
50	80
51	84
52	88
53	85
54	51
55	46
56	90
57	91
58	99
59	52
60	95
61	54
62	98
63	100
64	57
65	105
66	58
67	110
68	69
69	112
70	115
71	72
72	119
73	120
74	121