A345886 - cp's OEIS frontend

A345886 a(1) = 1, a(n) = a(n-1)/3 if a(n-1) is divisible by 3, otherwise a(n) = n - a(n-1).

n	a(n)
1	1
2	1
3	2
4	2
5	3
6	1
7	6
8	2
9	7
10	3
11	1
12	11
13	2
14	12
15	4
16	12
17	4
18	14
19	5
20	15
21	5
22	17
23	6
24	2
25	23
26	3
27	1
28	27
29	9
30	3
31	1
32	31
33	2
34	32
35	3
36	1
37	36
38	12
39	4
40	36
41	12
42	4
43	39
44	13
45	32
46	14
47	33
48	11
49	38
50	12
51	4
52	48
53	16
54	38
55	17
56	39
57	13
58	45
59	15
60	5
61	56
62	6
63	2
64	62
65	3
66	1
67	66
68	22
69	47
70	23
71	48
72	16
73	57
74	19
75	56
76	20
77	57
78	19
79	60
80	20
81	61
82	21
83	7
84	77
85	8

[1, 1, 2, 2, 3, 1, 6, 2, 7, 3, 1, 11, 2, 12, 4, 12, 4, 14, 5, 15, 5, 17, 6, 2, 23, 3, 1, 27, 9, 3, 1, 31, 2, 32, 3, 1, 36, 12, 4, 36, 12, 4, 39, 13, 32, 14, 33, 11, 38, 12, 4, 48, 16, 38, 17, 39, 13, 45, 15, 5, 56, 6, 2, 62, 3, 1, 66, 22, 47, 23, 48, 16, 57, 19, 56, 20, 57, 19, 60, 20, 61, 21, 7, 77, 8]

cp's OEIS Frontend

A345886 a(1) = 1, a(n) = a(n-1)/3 if a(n-1) is divisible by 3, otherwise a(n) = n - a(n-1).

Table of values

List of values

n	a(n)
1	1
2	1
3	2
4	2
5	3
6	1
7	6
8	2
9	7
10	3
11	1
12	11
13	2
14	12
15	4
16	12
17	4
18	14
19	5
20	15
21	5
22	17
23	6
24	2
25	23
26	3
27	1
28	27
29	9
30	3
31	1
32	31
33	2
34	32
35	3
36	1
37	36
38	12
39	4
40	36
41	12
42	4
43	39
44	13
45	32
46	14
47	33
48	11
49	38
50	12
51	4
52	48
53	16
54	38
55	17
56	39
57	13
58	45
59	15
60	5
61	56
62	6
63	2
64	62
65	3
66	1
67	66
68	22
69	47
70	23
71	48
72	16
73	57
74	19
75	56
76	20
77	57
78	19
79	60
80	20
81	61
82	21
83	7
84	77
85	8

n	a(n)
1	1
2	1
3	2
4	2
5	3
6	1
7	6
8	2
9	7
10	3
11	1
12	11
13	2
14	12
15	4
16	12
17	4
18	14
19	5
20	15
21	5
22	17
23	6
24	2
25	23
26	3
27	1
28	27
29	9
30	3
31	1
32	31
33	2
34	32
35	3
36	1
37	36
38	12
39	4
40	36
41	12
42	4
43	39
44	13
45	32
46	14
47	33
48	11
49	38
50	12
51	4
52	48
53	16
54	38
55	17
56	39
57	13
58	45
59	15
60	5
61	56
62	6
63	2
64	62
65	3
66	1
67	66
68	22
69	47
70	23
71	48
72	16
73	57
74	19
75	56
76	20
77	57
78	19
79	60
80	20
81	61
82	21
83	7
84	77
85	8

n	a(n)
1	1
2	1
3	2
4	2
5	3
6	1
7	6
8	2
9	7
10	3
11	1
12	11
13	2
14	12
15	4
16	12
17	4
18	14
19	5
20	15
21	5
22	17
23	6
24	2
25	23
26	3
27	1
28	27
29	9
30	3
31	1
32	31
33	2
34	32
35	3
36	1
37	36
38	12
39	4
40	36
41	12
42	4
43	39
44	13
45	32
46	14
47	33
48	11
49	38
50	12
51	4
52	48
53	16
54	38
55	17
56	39
57	13
58	45
59	15
60	5
61	56
62	6
63	2
64	62
65	3
66	1
67	66
68	22
69	47
70	23
71	48
72	16
73	57
74	19
75	56
76	20
77	57
78	19
79	60
80	20
81	61
82	21
83	7
84	77
85	8