A274516 - cp's OEIS frontend

A274516 Place n equally-spaced points around a circle, labeled 0,1,2,...,n-1. For each i = 0..n-1 such that 5i != i mod n, draw an (undirected) chord from i to (5i mod n). Then a(n) is the total number of distinct chords.

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

[0, 0, 0, 1, 0, 4, 2, 6, 2, 7, 8, 10, 4, 12, 12, 13, 10, 16, 14, 18, 16, 19, 20, 22, 10, 24, 24, 25, 24, 28, 26, 30, 26, 31, 32, 34, 28, 36, 36, 37, 34, 40, 38, 42, 40, 43, 44, 46, 34, 48, 48, 49, 48, 52, 50, 54, 50, 55, 56, 58, 52, 60, 60]

cp's OEIS Frontend

A274516 Place n equally-spaced points around a circle, labeled 0,1,2,...,n-1. For each i = 0..n-1 such that 5i != i mod n, draw an (undirected) chord from i to (5i mod n). Then a(n) is the total number of distinct chords.

Table of values

List of values

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

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

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