A203648 - cp's OEIS frontend

A203648 a(n) = (1/4) * period of repeating sequence {S(j) mod 2n}, where S(j) is the sum of the first j squares.

n	a(n)
1	1
2	2
3	9
4	4
5	5
6	18
7	7
8	8
9	27
10	10
11	11
12	36
13	13
14	14
15	45
16	16
17	17
18	54
19	19
20	20
21	63
22	22
23	23
24	72
25	25
26	26
27	81
28	28
29	29
30	90
31	31
32	32
33	99
34	34
35	35
36	108
37	37
38	38
39	117
40	40
41	41
42	126
43	43
44	44
45	135
46	46
47	47
48	144
49	49
50	50
51	153
52	52
53	53
54	162
55	55
56	56
57	171
58	58
59	59
60	180
61	61
62	62
63	189
64	64
65	65

[1, 2, 9, 4, 5, 18, 7, 8, 27, 10, 11, 36, 13, 14, 45, 16, 17, 54, 19, 20, 63, 22, 23, 72, 25, 26, 81, 28, 29, 90, 31, 32, 99, 34, 35, 108, 37, 38, 117, 40, 41, 126, 43, 44, 135, 46, 47, 144, 49, 50, 153, 52, 53, 162, 55, 56, 171, 58, 59, 180, 61, 62, 189, 64, 65]

cp's OEIS Frontend

A203648 a(n) = (1/4) * period of repeating sequence {S(j) mod 2n}, where S(j) is the sum of the first j squares.

Table of values

List of values

n	a(n)
1	1
2	2
3	9
4	4
5	5
6	18
7	7
8	8
9	27
10	10
11	11
12	36
13	13
14	14
15	45
16	16
17	17
18	54
19	19
20	20
21	63
22	22
23	23
24	72
25	25
26	26
27	81
28	28
29	29
30	90
31	31
32	32
33	99
34	34
35	35
36	108
37	37
38	38
39	117
40	40
41	41
42	126
43	43
44	44
45	135
46	46
47	47
48	144
49	49
50	50
51	153
52	52
53	53
54	162
55	55
56	56
57	171
58	58
59	59
60	180
61	61
62	62
63	189
64	64
65	65

n	a(n)
1	1
2	2
3	9
4	4
5	5
6	18
7	7
8	8
9	27
10	10
11	11
12	36
13	13
14	14
15	45
16	16
17	17
18	54
19	19
20	20
21	63
22	22
23	23
24	72
25	25
26	26
27	81
28	28
29	29
30	90
31	31
32	32
33	99
34	34
35	35
36	108
37	37
38	38
39	117
40	40
41	41
42	126
43	43
44	44
45	135
46	46
47	47
48	144
49	49
50	50
51	153
52	52
53	53
54	162
55	55
56	56
57	171
58	58
59	59
60	180
61	61
62	62
63	189
64	64
65	65

n	a(n)
1	1
2	2
3	9
4	4
5	5
6	18
7	7
8	8
9	27
10	10
11	11
12	36
13	13
14	14
15	45
16	16
17	17
18	54
19	19
20	20
21	63
22	22
23	23
24	72
25	25
26	26
27	81
28	28
29	29
30	90
31	31
32	32
33	99
34	34
35	35
36	108
37	37
38	38
39	117
40	40
41	41
42	126
43	43
44	44
45	135
46	46
47	47
48	144
49	49
50	50
51	153
52	52
53	53
54	162
55	55
56	56
57	171
58	58
59	59
60	180
61	61
62	62
63	189
64	64
65	65