A362631 - cp's OEIS frontend

A362631 Lexicographically earliest infinite sequence of distinct positive integers with a(n) = n for n <= 3, and for n > 3 a(n) is the least novel multiple of the greatest prime divisor of a(n-2) which does not divide a(n-1).

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	5
7	9
8	10
9	12
10	15
11	8
12	20
13	7
14	25
15	14
16	30
17	21
18	35
19	18
20	28
21	24
22	42
23	11
24	49
25	22
26	56
27	33
28	63
29	44
30	70
31	55
32	77
33	40
34	66
35	45
36	88
37	50
38	99
39	60
40	110
41	27
42	121
43	36
44	132
45	13
46	143
47	16
48	26
49	17
50	39
51	34
52	52
53	51
54	65
55	68
56	78
57	85
58	91
59	102
60	104
61	119
62	117
63	136
64	130
65	153
66	156
67	170
68	169
69	187
70	182
71	204
72	195
73	221
74	75
75	238
76	80
77	255
78	32
79	272
80	19

[1, 2, 3, 4, 6, 5, 9, 10, 12, 15, 8, 20, 7, 25, 14, 30, 21, 35, 18, 28, 24, 42, 11, 49, 22, 56, 33, 63, 44, 70, 55, 77, 40, 66, 45, 88, 50, 99, 60, 110, 27, 121, 36, 132, 13, 143, 16, 26, 17, 39, 34, 52, 51, 65, 68, 78, 85, 91, 102, 104, 119, 117, 136, 130, 153, 156, 170, 169, 187, 182, 204, 195, 221, 75, 238, 80, 255, 32, 272, 19]

cp's OEIS Frontend

A362631 Lexicographically earliest infinite sequence of distinct positive integers with a(n) = n for n <= 3, and for n > 3 a(n) is the least novel multiple of the greatest prime divisor of a(n-2) which does not divide a(n-1).

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	5
7	9
8	10
9	12
10	15
11	8
12	20
13	7
14	25
15	14
16	30
17	21
18	35
19	18
20	28
21	24
22	42
23	11
24	49
25	22
26	56
27	33
28	63
29	44
30	70
31	55
32	77
33	40
34	66
35	45
36	88
37	50
38	99
39	60
40	110
41	27
42	121
43	36
44	132
45	13
46	143
47	16
48	26
49	17
50	39
51	34
52	52
53	51
54	65
55	68
56	78
57	85
58	91
59	102
60	104
61	119
62	117
63	136
64	130
65	153
66	156
67	170
68	169
69	187
70	182
71	204
72	195
73	221
74	75
75	238
76	80
77	255
78	32
79	272
80	19

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	5
7	9
8	10
9	12
10	15
11	8
12	20
13	7
14	25
15	14
16	30
17	21
18	35
19	18
20	28
21	24
22	42
23	11
24	49
25	22
26	56
27	33
28	63
29	44
30	70
31	55
32	77
33	40
34	66
35	45
36	88
37	50
38	99
39	60
40	110
41	27
42	121
43	36
44	132
45	13
46	143
47	16
48	26
49	17
50	39
51	34
52	52
53	51
54	65
55	68
56	78
57	85
58	91
59	102
60	104
61	119
62	117
63	136
64	130
65	153
66	156
67	170
68	169
69	187
70	182
71	204
72	195
73	221
74	75
75	238
76	80
77	255
78	32
79	272
80	19

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	5
7	9
8	10
9	12
10	15
11	8
12	20
13	7
14	25
15	14
16	30
17	21
18	35
19	18
20	28
21	24
22	42
23	11
24	49
25	22
26	56
27	33
28	63
29	44
30	70
31	55
32	77
33	40
34	66
35	45
36	88
37	50
38	99
39	60
40	110
41	27
42	121
43	36
44	132
45	13
46	143
47	16
48	26
49	17
50	39
51	34
52	52
53	51
54	65
55	68
56	78
57	85
58	91
59	102
60	104
61	119
62	117
63	136
64	130
65	153
66	156
67	170
68	169
69	187
70	182
71	204
72	195
73	221
74	75
75	238
76	80
77	255
78	32
79	272
80	19