A049808 - cp's OEIS frontend

A049808 a(n)=number of Farey fractions of order n that are <=1/4; cf. A049805.

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	11
12	12
13	15
14	17
15	19
16	21
17	25
18	26
19	30
20	32
21	36
22	39
23	44
24	46
25	51
26	54
27	58
28	61
29	68
30	70
31	77
32	81
33	87
34	91
35	97
36	100
37	109
38	114
39	120
40	124
41	134
42	136
43	146
44	151
45	157
46	163
47	174
48	178
49	189
50	194
51	202
52	208
53	221
54	226
55	236
56	242

[1, 1, 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 15, 17, 19, 21, 25, 26, 30, 32, 36, 39, 44, 46, 51, 54, 58, 61, 68, 70, 77, 81, 87, 91, 97, 100, 109, 114, 120, 124, 134, 136, 146, 151, 157, 163, 174, 178, 189, 194, 202, 208, 221, 226, 236, 242]

cp's OEIS Frontend

A049808 a(n)=number of Farey fractions of order n that are <=1/4; cf. A049805.

Table of values

List of values

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	11
12	12
13	15
14	17
15	19
16	21
17	25
18	26
19	30
20	32
21	36
22	39
23	44
24	46
25	51
26	54
27	58
28	61
29	68
30	70
31	77
32	81
33	87
34	91
35	97
36	100
37	109
38	114
39	120
40	124
41	134
42	136
43	146
44	151
45	157
46	163
47	174
48	178
49	189
50	194
51	202
52	208
53	221
54	226
55	236
56	242

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	11
12	12
13	15
14	17
15	19
16	21
17	25
18	26
19	30
20	32
21	36
22	39
23	44
24	46
25	51
26	54
27	58
28	61
29	68
30	70
31	77
32	81
33	87
34	91
35	97
36	100
37	109
38	114
39	120
40	124
41	134
42	136
43	146
44	151
45	157
46	163
47	174
48	178
49	189
50	194
51	202
52	208
53	221
54	226
55	236
56	242

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	11
12	12
13	15
14	17
15	19
16	21
17	25
18	26
19	30
20	32
21	36
22	39
23	44
24	46
25	51
26	54
27	58
28	61
29	68
30	70
31	77
32	81
33	87
34	91
35	97
36	100
37	109
38	114
39	120
40	124
41	134
42	136
43	146
44	151
45	157
46	163
47	174
48	178
49	189
50	194
51	202
52	208
53	221
54	226
55	236
56	242