A074871 - cp's OEIS frontend

A074871 Start with n and repeatedly apply the map k -> T(k) = A053837(k) + A171765(k); a(n) is the number of steps (at least one) until a prime is reached, or 0 if no prime is ever reached.

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

[0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 2, 1, 0, 1, 1, 0, 1, 0, 1, 2, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 2, 1, 0, 0, 0, 1, 0, 1, 0, 1, 2, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 0, 1, 2, 2, 0, 1, 3, 2, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 0, 1, 2, 2, 2, 1, 2, 1, 2, 1, 0, 0, 1, 1, 2, 3, 1, 2, 1, 1, 0, 1, 1, 0, 1, 0]

cp's OEIS Frontend

A074871 Start with n and repeatedly apply the map k -> T(k) = A053837(k) + A171765(k); a(n) is the number of steps (at least one) until a prime is reached, or 0 if no prime is ever reached.

Table of values

List of values

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

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

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