A006667 - cp's OEIS frontend

A006667 Number of tripling steps to reach 1 from n in '3x+1' problem, or -1 if 1 is never reached.

n	a(n)
1	0
2	0
3	2
4	0
5	1
6	2
7	5
8	0
9	6
10	1
11	4
12	2
13	2
14	5
15	5
16	0
17	3
18	6
19	6
20	1
21	1
22	4
23	4
24	2
25	7
26	2
27	41
28	5
29	5
30	5
31	39
32	0
33	8
34	3
35	3
36	6
37	6
38	6
39	11
40	1
41	40
42	1
43	9
44	4
45	4
46	4
47	38
48	2
49	7
50	7
51	7
52	2
53	2
54	41
55	41
56	5
57	10
58	5
59	10
60	5
61	5
62	39
63	39
64	0
65	8
66	8
67	8
68	3
69	3
70	3
71	37
72	6
73	42
74	6
75	3
76	6
77	6
78	11
79	11
80	1
81	6
82	40
83	40
84	1
85	1
86	9
87	9
88	4
89	9
90	4
91	33
92	4
93	4
94	38

[0, 0, 2, 0, 1, 2, 5, 0, 6, 1, 4, 2, 2, 5, 5, 0, 3, 6, 6, 1, 1, 4, 4, 2, 7, 2, 41, 5, 5, 5, 39, 0, 8, 3, 3, 6, 6, 6, 11, 1, 40, 1, 9, 4, 4, 4, 38, 2, 7, 7, 7, 2, 2, 41, 41, 5, 10, 5, 10, 5, 5, 39, 39, 0, 8, 8, 8, 3, 3, 3, 37, 6, 42, 6, 3, 6, 6, 11, 11, 1, 6, 40, 40, 1, 1, 9, 9, 4, 9, 4, 33, 4, 4, 38]

cp's OEIS Frontend

A006667 Number of tripling steps to reach 1 from n in '3x+1' problem, or -1 if 1 is never reached.

Table of values

List of values

n	a(n)
1	0
2	0
3	2
4	0
5	1
6	2
7	5
8	0
9	6
10	1
11	4
12	2
13	2
14	5
15	5
16	0
17	3
18	6
19	6
20	1
21	1
22	4
23	4
24	2
25	7
26	2
27	41
28	5
29	5
30	5
31	39
32	0
33	8
34	3
35	3
36	6
37	6
38	6
39	11
40	1
41	40
42	1
43	9
44	4
45	4
46	4
47	38
48	2
49	7
50	7
51	7
52	2
53	2
54	41
55	41
56	5
57	10
58	5
59	10
60	5
61	5
62	39
63	39
64	0
65	8
66	8
67	8
68	3
69	3
70	3
71	37
72	6
73	42
74	6
75	3
76	6
77	6
78	11
79	11
80	1
81	6
82	40
83	40
84	1
85	1
86	9
87	9
88	4
89	9
90	4
91	33
92	4
93	4
94	38

n	a(n)
1	0
2	0
3	2
4	0
5	1
6	2
7	5
8	0
9	6
10	1
11	4
12	2
13	2
14	5
15	5
16	0
17	3
18	6
19	6
20	1
21	1
22	4
23	4
24	2
25	7
26	2
27	41
28	5
29	5
30	5
31	39
32	0
33	8
34	3
35	3
36	6
37	6
38	6
39	11
40	1
41	40
42	1
43	9
44	4
45	4
46	4
47	38
48	2
49	7
50	7
51	7
52	2
53	2
54	41
55	41
56	5
57	10
58	5
59	10
60	5
61	5
62	39
63	39
64	0
65	8
66	8
67	8
68	3
69	3
70	3
71	37
72	6
73	42
74	6
75	3
76	6
77	6
78	11
79	11
80	1
81	6
82	40
83	40
84	1
85	1
86	9
87	9
88	4
89	9
90	4
91	33
92	4
93	4
94	38

n	a(n)
1	0
2	0
3	2
4	0
5	1
6	2
7	5
8	0
9	6
10	1
11	4
12	2
13	2
14	5
15	5
16	0
17	3
18	6
19	6
20	1
21	1
22	4
23	4
24	2
25	7
26	2
27	41
28	5
29	5
30	5
31	39
32	0
33	8
34	3
35	3
36	6
37	6
38	6
39	11
40	1
41	40
42	1
43	9
44	4
45	4
46	4
47	38
48	2
49	7
50	7
51	7
52	2
53	2
54	41
55	41
56	5
57	10
58	5
59	10
60	5
61	5
62	39
63	39
64	0
65	8
66	8
67	8
68	3
69	3
70	3
71	37
72	6
73	42
74	6
75	3
76	6
77	6
78	11
79	11
80	1
81	6
82	40
83	40
84	1
85	1
86	9
87	9
88	4
89	9
90	4
91	33
92	4
93	4
94	38