A343156 - cp's OEIS frontend

A343156 Starting at n, a(n) = number of iterations of the map x -> A084317(x) (concatenate distinct prime factors of x) required to reach a prime, or -1 if no prime is ever reached.

n	a(n)
2	0
3	0
4	1
5	0
6	1
7	0
8	1
9	1
10	2
11	0
12	1
13	0
14	2
15	4
16	1
17	0
18	1
19	0
20	2
21	1
22	1
23	0
24	1
25	1
26	4
27	1
28	2
29	0
30	2
31	0
32	1
33	1
34	5
35	3
36	1
37	0
38	2
39	1
40	2
41	0
42	2
43	0
44	1
45	4
46	1
47	0
48	1
49	1
50	2
51	1
52	4
53	0
54	1
55	2
56	2
57	2
58	1
59	0
60	2
61	0
62	3
63	1
64	1
65	3
66	1
67	0
68	5
69	3
70	1
71	0
72	1
73	0
74	2
75	4
76	2
77	2
78	2
79	0
80	2
81	1
82	1
83	0
84	2
85	3
86	2
87	3
88	1
89	0
90	2
91	64
92	1
93	1
94	2
95	4
96	1
97	0
98	2
99	1
100	2

[0, 0, 1, 0, 1, 0, 1, 1, 2, 0, 1, 0, 2, 4, 1, 0, 1, 0, 2, 1, 1, 0, 1, 1, 4, 1, 2, 0, 2, 0, 1, 1, 5, 3, 1, 0, 2, 1, 2, 0, 2, 0, 1, 4, 1, 0, 1, 1, 2, 1, 4, 0, 1, 2, 2, 2, 1, 0, 2, 0, 3, 1, 1, 3, 1, 0, 5, 3, 1, 0, 1, 0, 2, 4, 2, 2, 2, 0, 2, 1, 1, 0, 2, 3, 2, 3, 1, 0, 2, 64, 1, 1, 2, 4, 1, 0, 2, 1, 2]

cp's OEIS Frontend

A343156 Starting at n, a(n) = number of iterations of the map x -> A084317(x) (concatenate distinct prime factors of x) required to reach a prime, or -1 if no prime is ever reached.

Table of values

List of values

n	a(n)
2	0
3	0
4	1
5	0
6	1
7	0
8	1
9	1
10	2
11	0
12	1
13	0
14	2
15	4
16	1
17	0
18	1
19	0
20	2
21	1
22	1
23	0
24	1
25	1
26	4
27	1
28	2
29	0
30	2
31	0
32	1
33	1
34	5
35	3
36	1
37	0
38	2
39	1
40	2
41	0
42	2
43	0
44	1
45	4
46	1
47	0
48	1
49	1
50	2
51	1
52	4
53	0
54	1
55	2
56	2
57	2
58	1
59	0
60	2
61	0
62	3
63	1
64	1
65	3
66	1
67	0
68	5
69	3
70	1
71	0
72	1
73	0
74	2
75	4
76	2
77	2
78	2
79	0
80	2
81	1
82	1
83	0
84	2
85	3
86	2
87	3
88	1
89	0
90	2
91	64
92	1
93	1
94	2
95	4
96	1
97	0
98	2
99	1
100	2

n	a(n)
2	0
3	0
4	1
5	0
6	1
7	0
8	1
9	1
10	2
11	0
12	1
13	0
14	2
15	4
16	1
17	0
18	1
19	0
20	2
21	1
22	1
23	0
24	1
25	1
26	4
27	1
28	2
29	0
30	2
31	0
32	1
33	1
34	5
35	3
36	1
37	0
38	2
39	1
40	2
41	0
42	2
43	0
44	1
45	4
46	1
47	0
48	1
49	1
50	2
51	1
52	4
53	0
54	1
55	2
56	2
57	2
58	1
59	0
60	2
61	0
62	3
63	1
64	1
65	3
66	1
67	0
68	5
69	3
70	1
71	0
72	1
73	0
74	2
75	4
76	2
77	2
78	2
79	0
80	2
81	1
82	1
83	0
84	2
85	3
86	2
87	3
88	1
89	0
90	2
91	64
92	1
93	1
94	2
95	4
96	1
97	0
98	2
99	1
100	2

n	a(n)
2	0
3	0
4	1
5	0
6	1
7	0
8	1
9	1
10	2
11	0
12	1
13	0
14	2
15	4
16	1
17	0
18	1
19	0
20	2
21	1
22	1
23	0
24	1
25	1
26	4
27	1
28	2
29	0
30	2
31	0
32	1
33	1
34	5
35	3
36	1
37	0
38	2
39	1
40	2
41	0
42	2
43	0
44	1
45	4
46	1
47	0
48	1
49	1
50	2
51	1
52	4
53	0
54	1
55	2
56	2
57	2
58	1
59	0
60	2
61	0
62	3
63	1
64	1
65	3
66	1
67	0
68	5
69	3
70	1
71	0
72	1
73	0
74	2
75	4
76	2
77	2
78	2
79	0
80	2
81	1
82	1
83	0
84	2
85	3
86	2
87	3
88	1
89	0
90	2
91	64
92	1
93	1
94	2
95	4
96	1
97	0
98	2
99	1
100	2