A078350 - cp's OEIS frontend

A078350 Number of primes in {n, f(n), f(f(n)), ..., 1}, where f is the Collatz function defined by f(x) = x/2 if x is even; f(x) = 3x + 1 if x is odd.

n	a(n)
1	0
2	1
3	3
4	1
5	2
6	3
7	6
8	1
9	6
10	2
11	5
12	3
13	3
14	6
15	4
16	1
17	4
18	6
19	7
20	2
21	1
22	5
23	4
24	3
25	7
26	3
27	25
28	6
29	6
30	4
31	24
32	1
33	7
34	4
35	3
36	6
37	7
38	7
39	11
40	2
41	25
42	1
43	8
44	5
45	4
46	4
47	23
48	3
49	7
50	7
51	6
52	3
53	3
54	25
55	24
56	6
57	8
58	6
59	11
60	4
61	5
62	24
63	20
64	1
65	7
66	7
67	9
68	4
69	3
70	3
71	22
72	6
73	25
74	7
75	2
76	7
77	6
78	11
79	11
80	2
81	5
82	25
83	24
84	1
85	1
86	8
87	9
88	5
89	10
90	4
91	20
92	4
93	3
94	23
95	20

[0, 1, 3, 1, 2, 3, 6, 1, 6, 2, 5, 3, 3, 6, 4, 1, 4, 6, 7, 2, 1, 5, 4, 3, 7, 3, 25, 6, 6, 4, 24, 1, 7, 4, 3, 6, 7, 7, 11, 2, 25, 1, 8, 5, 4, 4, 23, 3, 7, 7, 6, 3, 3, 25, 24, 6, 8, 6, 11, 4, 5, 24, 20, 1, 7, 7, 9, 4, 3, 3, 22, 6, 25, 7, 2, 7, 6, 11, 11, 2, 5, 25, 24, 1, 1, 8, 9, 5, 10, 4, 20, 4, 3, 23, 20]

cp's OEIS Frontend

A078350 Number of primes in {n, f(n), f(f(n)), ..., 1}, where f is the Collatz function defined by f(x) = x/2 if x is even; f(x) = 3x + 1 if x is odd.

Table of values

List of values

n	a(n)
1	0
2	1
3	3
4	1
5	2
6	3
7	6
8	1
9	6
10	2
11	5
12	3
13	3
14	6
15	4
16	1
17	4
18	6
19	7
20	2
21	1
22	5
23	4
24	3
25	7
26	3
27	25
28	6
29	6
30	4
31	24
32	1
33	7
34	4
35	3
36	6
37	7
38	7
39	11
40	2
41	25
42	1
43	8
44	5
45	4
46	4
47	23
48	3
49	7
50	7
51	6
52	3
53	3
54	25
55	24
56	6
57	8
58	6
59	11
60	4
61	5
62	24
63	20
64	1
65	7
66	7
67	9
68	4
69	3
70	3
71	22
72	6
73	25
74	7
75	2
76	7
77	6
78	11
79	11
80	2
81	5
82	25
83	24
84	1
85	1
86	8
87	9
88	5
89	10
90	4
91	20
92	4
93	3
94	23
95	20

n	a(n)
1	0
2	1
3	3
4	1
5	2
6	3
7	6
8	1
9	6
10	2
11	5
12	3
13	3
14	6
15	4
16	1
17	4
18	6
19	7
20	2
21	1
22	5
23	4
24	3
25	7
26	3
27	25
28	6
29	6
30	4
31	24
32	1
33	7
34	4
35	3
36	6
37	7
38	7
39	11
40	2
41	25
42	1
43	8
44	5
45	4
46	4
47	23
48	3
49	7
50	7
51	6
52	3
53	3
54	25
55	24
56	6
57	8
58	6
59	11
60	4
61	5
62	24
63	20
64	1
65	7
66	7
67	9
68	4
69	3
70	3
71	22
72	6
73	25
74	7
75	2
76	7
77	6
78	11
79	11
80	2
81	5
82	25
83	24
84	1
85	1
86	8
87	9
88	5
89	10
90	4
91	20
92	4
93	3
94	23
95	20

n	a(n)
1	0
2	1
3	3
4	1
5	2
6	3
7	6
8	1
9	6
10	2
11	5
12	3
13	3
14	6
15	4
16	1
17	4
18	6
19	7
20	2
21	1
22	5
23	4
24	3
25	7
26	3
27	25
28	6
29	6
30	4
31	24
32	1
33	7
34	4
35	3
36	6
37	7
38	7
39	11
40	2
41	25
42	1
43	8
44	5
45	4
46	4
47	23
48	3
49	7
50	7
51	6
52	3
53	3
54	25
55	24
56	6
57	8
58	6
59	11
60	4
61	5
62	24
63	20
64	1
65	7
66	7
67	9
68	4
69	3
70	3
71	22
72	6
73	25
74	7
75	2
76	7
77	6
78	11
79	11
80	2
81	5
82	25
83	24
84	1
85	1
86	8
87	9
88	5
89	10
90	4
91	20
92	4
93	3
94	23
95	20