A055509 - cp's OEIS frontend

A055509 Number of odd primes in sequence obtained in 3x+1 (or Collatz) problem starting at n.

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

[0, 0, 2, 0, 1, 2, 5, 0, 5, 1, 4, 2, 2, 5, 3, 0, 3, 5, 6, 1, 0, 4, 3, 2, 6, 2, 24, 5, 5, 3, 23, 0, 6, 3, 2, 5, 6, 6, 10, 1, 24, 0, 7, 4, 3, 3, 22, 2, 6, 6, 5, 2, 2, 24, 23, 5, 7, 5, 10, 3, 4, 23, 19, 0, 6, 6, 8, 3, 2, 2, 21, 5, 24, 6, 1, 6, 5, 10, 10, 1, 4, 24, 23, 0, 0, 7, 8, 4, 9, 3, 19, 3, 2, 22, 19]

cp's OEIS Frontend

A055509 Number of odd primes in sequence obtained in 3x+1 (or Collatz) problem starting at n.

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

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

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