A326791 - cp's OEIS frontend

A326791 For n > 1, let f_n be the lexicographically earliest sequence of distinct positive terms such that f_n(1) = 1, f_n(2) = n, and for k > 2, f_n(k) divides f_n(k-2) + f_n(k-1); if f_n is finite, then a(n) is the number of terms of f_n, otherwise a(n) = -1; a(1) = 1.

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

[1, 39, 23, 5, 10, 9, 31, 8, 8, 8, 7, 8, 7, 9, 10, 29, 9, 38, 36, 13, 14, 13, 8, 12, 40, 19, 11, 25, 10, 15, 13, 18, 11, 5, 39, 36, 40, 37, 12, 25, 11, 12, 29, 30, 33, 25, 32, 5, 40, 25, 12, 25, 11, 21, 40, 27, 18, 19, 17, 9, 41, 18, 11, 5, 41, 37, 40, 12, 29]

cp's OEIS Frontend

A326791 For n > 1, let f_n be the lexicographically earliest sequence of distinct positive terms such that f_n(1) = 1, f_n(2) = n, and for k > 2, f_n(k) divides f_n(k-2) + f_n(k-1); if f_n is finite, then a(n) is the number of terms of f_n, otherwise a(n) = -1; a(1) = 1.

Table of values

List of values

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

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

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