A347088 - cp's OEIS frontend

A347088 a(n) = A055155(n) - d(n), where A055155(n) = Sum_{d|n} gcd(d, n/d) and d(n) gives the number of divisors of n.

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

[0, 0, 0, 1, 0, 0, 0, 2, 2, 0, 0, 2, 0, 0, 0, 5, 0, 4, 0, 2, 0, 0, 0, 4, 4, 0, 4, 2, 0, 0, 0, 8, 0, 0, 0, 11, 0, 0, 0, 4, 0, 0, 0, 2, 4, 0, 0, 10, 6, 8, 0, 2, 0, 8, 0, 4, 0, 0, 0, 4, 0, 0, 4, 15, 0, 0, 0, 2, 0, 0, 0, 18, 0, 0, 8, 2, 0, 0, 0, 10, 12, 0, 0, 4, 0, 0, 0, 4, 0, 8, 0, 2, 0, 0, 0, 16, 0, 12, 4, 19, 0, 0, 0, 4, 0]

cp's OEIS Frontend

A347088 a(n) = A055155(n) - d(n), where A055155(n) = Sum_{d|n} gcd(d, n/d) and d(n) gives the number of divisors of n.

Table of values

List of values

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

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

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