A332845 - cp's OEIS frontend

A332845 a(n) = (-1)^omega(n) * Sum_{k=1..n} (-1)^omega(n/gcd(n, k)), where omega = A001221.

n	a(n)
1	1
2	0
3	1
4	2
5	3
6	0
7	5
8	6
9	7
10	0
11	9
12	2
13	11
14	0
15	3
16	14
17	15
18	0
19	17
20	6
21	5
22	0
23	21
24	6
25	23
26	0
27	25
28	10
29	27
30	0
31	29
32	30
33	9
34	0
35	15
36	14
37	35
38	0
39	11
40	18
41	39
42	0
43	41
44	18
45	21
46	0
47	45
48	14
49	47
50	0
51	15
52	22
53	51
54	0
55	27
56	30
57	17
58	0
59	57
60	6
61	59
62	0
63	35
64	62
65	33
66	0
67	65
68	30
69	21
70	0
71	69
72	42
73	71

[1, 0, 1, 2, 3, 0, 5, 6, 7, 0, 9, 2, 11, 0, 3, 14, 15, 0, 17, 6, 5, 0, 21, 6, 23, 0, 25, 10, 27, 0, 29, 30, 9, 0, 15, 14, 35, 0, 11, 18, 39, 0, 41, 18, 21, 0, 45, 14, 47, 0, 15, 22, 51, 0, 27, 30, 17, 0, 57, 6, 59, 0, 35, 62, 33, 0, 65, 30, 21, 0, 69, 42, 71]

cp's OEIS Frontend

A332845 a(n) = (-1)^omega(n) * Sum_{k=1..n} (-1)^omega(n/gcd(n, k)), where omega = A001221.

Table of values

List of values

n	a(n)
1	1
2	0
3	1
4	2
5	3
6	0
7	5
8	6
9	7
10	0
11	9
12	2
13	11
14	0
15	3
16	14
17	15
18	0
19	17
20	6
21	5
22	0
23	21
24	6
25	23
26	0
27	25
28	10
29	27
30	0
31	29
32	30
33	9
34	0
35	15
36	14
37	35
38	0
39	11
40	18
41	39
42	0
43	41
44	18
45	21
46	0
47	45
48	14
49	47
50	0
51	15
52	22
53	51
54	0
55	27
56	30
57	17
58	0
59	57
60	6
61	59
62	0
63	35
64	62
65	33
66	0
67	65
68	30
69	21
70	0
71	69
72	42
73	71

n	a(n)
1	1
2	0
3	1
4	2
5	3
6	0
7	5
8	6
9	7
10	0
11	9
12	2
13	11
14	0
15	3
16	14
17	15
18	0
19	17
20	6
21	5
22	0
23	21
24	6
25	23
26	0
27	25
28	10
29	27
30	0
31	29
32	30
33	9
34	0
35	15
36	14
37	35
38	0
39	11
40	18
41	39
42	0
43	41
44	18
45	21
46	0
47	45
48	14
49	47
50	0
51	15
52	22
53	51
54	0
55	27
56	30
57	17
58	0
59	57
60	6
61	59
62	0
63	35
64	62
65	33
66	0
67	65
68	30
69	21
70	0
71	69
72	42
73	71

n	a(n)
1	1
2	0
3	1
4	2
5	3
6	0
7	5
8	6
9	7
10	0
11	9
12	2
13	11
14	0
15	3
16	14
17	15
18	0
19	17
20	6
21	5
22	0
23	21
24	6
25	23
26	0
27	25
28	10
29	27
30	0
31	29
32	30
33	9
34	0
35	15
36	14
37	35
38	0
39	11
40	18
41	39
42	0
43	41
44	18
45	21
46	0
47	45
48	14
49	47
50	0
51	15
52	22
53	51
54	0
55	27
56	30
57	17
58	0
59	57
60	6
61	59
62	0
63	35
64	62
65	33
66	0
67	65
68	30
69	21
70	0
71	69
72	42
73	71