A077814 - cp's OEIS frontend

A077814 a(n) = #{0<=k<=n: mod(k*n,4)=2}.

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

[0, 0, 1, 1, 0, 1, 3, 2, 0, 2, 5, 3, 0, 3, 7, 4, 0, 4, 9, 5, 0, 5, 11, 6, 0, 6, 13, 7, 0, 7, 15, 8, 0, 8, 17, 9, 0, 9, 19, 10, 0, 10, 21, 11, 0, 11, 23, 12, 0, 12, 25, 13, 0, 13, 27, 14, 0, 14, 29, 15, 0, 15, 31, 16, 0, 16, 33, 17, 0, 17, 35, 18, 0, 18, 37, 19, 0, 19, 39, 20, 0, 20, 41, 21, 0]

cp's OEIS Frontend

A077814 a(n) = #{0<=k<=n: mod(k*n,4)=2}.

Table of values

List of values

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

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

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