A300270 - cp's OEIS frontend

A300270 a(n) = Sum_{1 <= i <= j <= n} mu(ij)floor((n/i)/j).

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

[1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 4, 4, 5, 6, 6, 6, 7, 7, 8, 9, 10, 10, 11, 11, 12, 12, 13, 13, 13, 13, 13, 14, 15, 16, 17, 17, 18, 19, 20, 20, 20, 20, 21, 22, 23, 23, 24, 24, 25, 26, 27, 27, 28, 29, 30, 31, 32, 32, 32, 32, 33, 34, 34, 35, 35, 35, 36, 37, 37, 37, 38, 38, 39, 40, 41, 42, 42, 42, 43, 43, 44, 44, 44, 45, 46, 47, 48, 48, 48]

cp's OEIS Frontend

A300270 a(n) = Sum_{1 <= i <= j <= n} mu(ij)floor((n/i)/j).

Table of values

List of values

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

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

cp's OEIS Frontend

A300270 a(n) = Sum_{1 <= i <= j <= n} mu(i*j)*floor((n/i)/j).

Table of values

List of values

A300270 a(n) = Sum_{1 <= i <= j <= n} mu(ij)floor((n/i)/j).

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