A373545 - cp's OEIS frontend

A373545 a(1) = 1, a(2) = 2; for n > 2, a(n) is the smallest unused positive number that shares a factor with a(n-1) if a(n-1) is odd otherwise is coprime to a(n-1) if a(n-1) is even.

n	a(n)
1	1
2	2
3	3
4	6
5	5
6	10
7	7
8	14
9	9
10	12
11	11
12	22
13	13
14	26
15	15
16	18
17	17
18	34
19	19
20	38
21	21
22	24
23	23
24	46
25	25
26	20
27	27
28	30
29	29
30	58
31	31
32	62
33	33
34	36
35	35
36	28
37	37
38	74
39	39
40	42
41	41
42	82
43	43
44	86
45	45
46	40
47	47
48	94
49	49
50	56
51	51
52	48
53	53
54	106
55	55
56	44
57	57
58	54
59	59
60	118
61	61
62	122
63	63
64	60
65	67
66	134
67	65
68	50
69	69
70	66
71	71
72	142
73	73
74	146

[1, 2, 3, 6, 5, 10, 7, 14, 9, 12, 11, 22, 13, 26, 15, 18, 17, 34, 19, 38, 21, 24, 23, 46, 25, 20, 27, 30, 29, 58, 31, 62, 33, 36, 35, 28, 37, 74, 39, 42, 41, 82, 43, 86, 45, 40, 47, 94, 49, 56, 51, 48, 53, 106, 55, 44, 57, 54, 59, 118, 61, 122, 63, 60, 67, 134, 65, 50, 69, 66, 71, 142, 73, 146]

cp's OEIS Frontend

A373545 a(1) = 1, a(2) = 2; for n > 2, a(n) is the smallest unused positive number that shares a factor with a(n-1) if a(n-1) is odd otherwise is coprime to a(n-1) if a(n-1) is even.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	6
5	5
6	10
7	7
8	14
9	9
10	12
11	11
12	22
13	13
14	26
15	15
16	18
17	17
18	34
19	19
20	38
21	21
22	24
23	23
24	46
25	25
26	20
27	27
28	30
29	29
30	58
31	31
32	62
33	33
34	36
35	35
36	28
37	37
38	74
39	39
40	42
41	41
42	82
43	43
44	86
45	45
46	40
47	47
48	94
49	49
50	56
51	51
52	48
53	53
54	106
55	55
56	44
57	57
58	54
59	59
60	118
61	61
62	122
63	63
64	60
65	67
66	134
67	65
68	50
69	69
70	66
71	71
72	142
73	73
74	146

n	a(n)
1	1
2	2
3	3
4	6
5	5
6	10
7	7
8	14
9	9
10	12
11	11
12	22
13	13
14	26
15	15
16	18
17	17
18	34
19	19
20	38
21	21
22	24
23	23
24	46
25	25
26	20
27	27
28	30
29	29
30	58
31	31
32	62
33	33
34	36
35	35
36	28
37	37
38	74
39	39
40	42
41	41
42	82
43	43
44	86
45	45
46	40
47	47
48	94
49	49
50	56
51	51
52	48
53	53
54	106
55	55
56	44
57	57
58	54
59	59
60	118
61	61
62	122
63	63
64	60
65	67
66	134
67	65
68	50
69	69
70	66
71	71
72	142
73	73
74	146

n	a(n)
1	1
2	2
3	3
4	6
5	5
6	10
7	7
8	14
9	9
10	12
11	11
12	22
13	13
14	26
15	15
16	18
17	17
18	34
19	19
20	38
21	21
22	24
23	23
24	46
25	25
26	20
27	27
28	30
29	29
30	58
31	31
32	62
33	33
34	36
35	35
36	28
37	37
38	74
39	39
40	42
41	41
42	82
43	43
44	86
45	45
46	40
47	47
48	94
49	49
50	56
51	51
52	48
53	53
54	106
55	55
56	44
57	57
58	54
59	59
60	118
61	61
62	122
63	63
64	60
65	67
66	134
67	65
68	50
69	69
70	66
71	71
72	142
73	73
74	146