A377120 - cp's OEIS frontend

A377120 a(n) = number of iterations of x -> 2 x + 3 to reach a nonprime, starting with prime(n) .

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

[4, 1, 4, 3, 1, 3, 2, 2, 1, 2, 1, 1, 1, 3, 6, 2, 1, 1, 6, 1, 2, 1, 1, 2, 5, 1, 1, 1, 1, 3, 2, 1, 5, 2, 1, 1, 2, 1, 3, 3, 1, 1, 1, 2, 4, 2, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 2, 1, 4, 1, 2, 1, 5, 1, 1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 2, 2, 1, 3, 1, 2, 1, 1, 1, 1, 2, 1]

cp's OEIS Frontend

A377120 a(n) = number of iterations of x -> 2 x + 3 to reach a nonprime, starting with prime(n) .

Table of values

List of values

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

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

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