A382872 - cp's OEIS frontend

A382872 For n >= 1, a(n) is the number of divisors of the Pillai's arithmetical function: Sum_{k=1..n} gcd(k, n) (A018804).

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

[1, 2, 2, 4, 3, 4, 2, 6, 4, 4, 4, 8, 3, 4, 6, 10, 4, 6, 2, 12, 4, 6, 6, 9, 4, 6, 5, 8, 4, 8, 2, 10, 8, 6, 6, 16, 2, 4, 4, 18, 5, 8, 4, 16, 8, 8, 4, 20, 4, 8, 8, 12, 8, 6, 8, 12, 4, 6, 6, 24, 3, 4, 8, 9, 9, 12, 4, 16, 9, 8, 4, 24, 4, 4, 6, 8, 8, 8, 2, 20]

cp's OEIS Frontend

A382872 For n >= 1, a(n) is the number of divisors of the Pillai's arithmetical function: Sum_{k=1..n} gcd(k, n) (A018804).

Table of values

List of values

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

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

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