A163107 - cp's OEIS frontend

A163107 a(n) = tau(tau(sigma(n))), where tau = A000005, the number of divisors, and sigma = A000203, the sum of divisors of n.

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

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

cp's OEIS Frontend

A163107 a(n) = tau(tau(sigma(n))), where tau = A000005, the number of divisors, and sigma = A000203, the sum of divisors of n.

Table of values

List of values

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

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

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