A349493 - cp's OEIS frontend

A349493 a(1)=1, a(2)=2; for n > 2, a(n) is the smallest unused positive number such that gcd(a(n-2)+a(n-1), a(n)) > 1 while gcd(a(n-2), a(n)) = 1 and gcd(a(n-1), a(n)) = 1.

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	9
7	13
8	8
9	7
10	15
11	11
12	14
13	25
14	27
15	16
16	43
17	59
18	6
19	35
20	41
21	12
22	53
23	55
24	18
25	73
26	49
27	10
28	177
29	17
30	20
31	37
32	19
33	21
34	22
35	215
36	39
37	28
38	67
39	45
40	26
41	71
42	97
43	24
44	77
45	101
46	30
47	131
48	23
49	32
50	33
51	65
52	34
53	57
54	91
55	40
56	393
57	433
58	38
59	51
60	89
61	44
62	63
63	107
64	46
65	75
66	121
67	52
68	173
69	69
70	50
71	119
72	117
73	58
74	85

[1, 2, 3, 5, 4, 9, 13, 8, 7, 15, 11, 14, 25, 27, 16, 43, 59, 6, 35, 41, 12, 53, 55, 18, 73, 49, 10, 177, 17, 20, 37, 19, 21, 22, 215, 39, 28, 67, 45, 26, 71, 97, 24, 77, 101, 30, 131, 23, 32, 33, 65, 34, 57, 91, 40, 393, 433, 38, 51, 89, 44, 63, 107, 46, 75, 121, 52, 173, 69, 50, 119, 117, 58, 85]

cp's OEIS Frontend

A349493 a(1)=1, a(2)=2; for n > 2, a(n) is the smallest unused positive number such that gcd(a(n-2)+a(n-1), a(n)) > 1 while gcd(a(n-2), a(n)) = 1 and gcd(a(n-1), a(n)) = 1.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	9
7	13
8	8
9	7
10	15
11	11
12	14
13	25
14	27
15	16
16	43
17	59
18	6
19	35
20	41
21	12
22	53
23	55
24	18
25	73
26	49
27	10
28	177
29	17
30	20
31	37
32	19
33	21
34	22
35	215
36	39
37	28
38	67
39	45
40	26
41	71
42	97
43	24
44	77
45	101
46	30
47	131
48	23
49	32
50	33
51	65
52	34
53	57
54	91
55	40
56	393
57	433
58	38
59	51
60	89
61	44
62	63
63	107
64	46
65	75
66	121
67	52
68	173
69	69
70	50
71	119
72	117
73	58
74	85

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	9
7	13
8	8
9	7
10	15
11	11
12	14
13	25
14	27
15	16
16	43
17	59
18	6
19	35
20	41
21	12
22	53
23	55
24	18
25	73
26	49
27	10
28	177
29	17
30	20
31	37
32	19
33	21
34	22
35	215
36	39
37	28
38	67
39	45
40	26
41	71
42	97
43	24
44	77
45	101
46	30
47	131
48	23
49	32
50	33
51	65
52	34
53	57
54	91
55	40
56	393
57	433
58	38
59	51
60	89
61	44
62	63
63	107
64	46
65	75
66	121
67	52
68	173
69	69
70	50
71	119
72	117
73	58
74	85

n	a(n)
1	1
2	2
3	3
4	5
5	4
6	9
7	13
8	8
9	7
10	15
11	11
12	14
13	25
14	27
15	16
16	43
17	59
18	6
19	35
20	41
21	12
22	53
23	55
24	18
25	73
26	49
27	10
28	177
29	17
30	20
31	37
32	19
33	21
34	22
35	215
36	39
37	28
38	67
39	45
40	26
41	71
42	97
43	24
44	77
45	101
46	30
47	131
48	23
49	32
50	33
51	65
52	34
53	57
54	91
55	40
56	393
57	433
58	38
59	51
60	89
61	44
62	63
63	107
64	46
65	75
66	121
67	52
68	173
69	69
70	50
71	119
72	117
73	58
74	85