A083647 - cp's OEIS frontend

A083647 For primes p: Number of steps to reach 2 when iterating f(p) = greatest prime divisor of p-1.

n	a(n)
1	0
2	1
3	1
4	2
5	2
6	2
7	1
8	2
9	3
10	3
11	2
12	2
13	2
14	3
15	4
16	3
17	4
18	2
19	3
20	3
21	2
22	3
23	3
24	3
25	2
26	2
27	2
28	4
29	2
30	3
31	3
32	3
33	2
34	4
35	3
36	2
37	3
38	2
39	4
40	4
41	4
42	2
43	3
44	2
45	3
46	3
47	3
48	3
49	4
50	3
51	4
52	2
53	2
54	2
55	1
56	4
57	4
58	2
59	4
60	3
61	5
62	3
63	2
64	3
65	3
66	4
67	3
68	3
69	5
70	4
71	3
72	5
73	3
74	3
75	3
76	4
77	3
78	3
79	2
80	2
81	3
82	3
83	4
84	2
85	3
86	2
87	3
88	3
89	4
90	3
91	5
92	3
93	2
94	3
95	4
96	3
97	4
98	3
99	4
100	2
101	3
102	5
103	4
104	4
105	3

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

cp's OEIS Frontend

A083647 For primes p: Number of steps to reach 2 when iterating f(p) = greatest prime divisor of p-1.

Table of values

List of values

n	a(n)
1	0
2	1
3	1
4	2
5	2
6	2
7	1
8	2
9	3
10	3
11	2
12	2
13	2
14	3
15	4
16	3
17	4
18	2
19	3
20	3
21	2
22	3
23	3
24	3
25	2
26	2
27	2
28	4
29	2
30	3
31	3
32	3
33	2
34	4
35	3
36	2
37	3
38	2
39	4
40	4
41	4
42	2
43	3
44	2
45	3
46	3
47	3
48	3
49	4
50	3
51	4
52	2
53	2
54	2
55	1
56	4
57	4
58	2
59	4
60	3
61	5
62	3
63	2
64	3
65	3
66	4
67	3
68	3
69	5
70	4
71	3
72	5
73	3
74	3
75	3
76	4
77	3
78	3
79	2
80	2
81	3
82	3
83	4
84	2
85	3
86	2
87	3
88	3
89	4
90	3
91	5
92	3
93	2
94	3
95	4
96	3
97	4
98	3
99	4
100	2
101	3
102	5
103	4
104	4
105	3

n	a(n)
1	0
2	1
3	1
4	2
5	2
6	2
7	1
8	2
9	3
10	3
11	2
12	2
13	2
14	3
15	4
16	3
17	4
18	2
19	3
20	3
21	2
22	3
23	3
24	3
25	2
26	2
27	2
28	4
29	2
30	3
31	3
32	3
33	2
34	4
35	3
36	2
37	3
38	2
39	4
40	4
41	4
42	2
43	3
44	2
45	3
46	3
47	3
48	3
49	4
50	3
51	4
52	2
53	2
54	2
55	1
56	4
57	4
58	2
59	4
60	3
61	5
62	3
63	2
64	3
65	3
66	4
67	3
68	3
69	5
70	4
71	3
72	5
73	3
74	3
75	3
76	4
77	3
78	3
79	2
80	2
81	3
82	3
83	4
84	2
85	3
86	2
87	3
88	3
89	4
90	3
91	5
92	3
93	2
94	3
95	4
96	3
97	4
98	3
99	4
100	2
101	3
102	5
103	4
104	4
105	3

n	a(n)
1	0
2	1
3	1
4	2
5	2
6	2
7	1
8	2
9	3
10	3
11	2
12	2
13	2
14	3
15	4
16	3
17	4
18	2
19	3
20	3
21	2
22	3
23	3
24	3
25	2
26	2
27	2
28	4
29	2
30	3
31	3
32	3
33	2
34	4
35	3
36	2
37	3
38	2
39	4
40	4
41	4
42	2
43	3
44	2
45	3
46	3
47	3
48	3
49	4
50	3
51	4
52	2
53	2
54	2
55	1
56	4
57	4
58	2
59	4
60	3
61	5
62	3
63	2
64	3
65	3
66	4
67	3
68	3
69	5
70	4
71	3
72	5
73	3
74	3
75	3
76	4
77	3
78	3
79	2
80	2
81	3
82	3
83	4
84	2
85	3
86	2
87	3
88	3
89	4
90	3
91	5
92	3
93	2
94	3
95	4
96	3
97	4
98	3
99	4
100	2
101	3
102	5
103	4
104	4
105	3