A072628 - cp's OEIS frontend

A072628 Number of divisors d of n such that d-1 is not prime.

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

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

cp's OEIS Frontend

A072628 Number of divisors d of n such that d-1 is not prime.

Table of values

List of values

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

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

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