A112505 - cp's OEIS frontend

A112505 Number of primitive prime factors of 10^n-1.

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

[1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 2, 1, 3, 1, 2, 2, 2, 2, 1, 2, 3, 3, 1, 1, 3, 2, 2, 3, 5, 3, 3, 5, 2, 3, 3, 1, 3, 1, 1, 2, 4, 3, 4, 3, 2, 4, 2, 1, 2, 3, 4, 2, 4, 2, 4, 2, 3, 2, 2, 3, 7, 1, 5, 4, 2, 2, 3, 3, 3, 2, 2, 3, 3, 3, 3, 2, 4, 4, 6, 2, 5, 2, 3, 2, 3, 3, 3, 2, 5, 3, 7, 3, 1, 3, 5, 4, 3, 2, 4, 4]

cp's OEIS Frontend

A112505 Number of primitive prime factors of 10^n-1.

Table of values

List of values

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

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

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