A308778 - cp's OEIS frontend

A308778 Central element(s) in the period of the continued fraction expansion of sqrt(n), or 0 if no such element exists, or -1 if n is a square.

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

[-1, -1, 0, 1, -1, 0, 2, 1, 1, -1, 0, 3, 2, 1, 2, 1, -1, 0, 4, 3, 2, 2, 4, 3, 1, -1, 0, 5, 2, 1, 2, 5, 1, 2, 4, 1, -1, 0, 6, 4, 3, 2, 2, 5, 2, 2, 6, 5, 1, -1, 0, 7, 2, 1, 6, 2, 2, 4, 1, 7, 2, 2, 6, 1, -1, 0, 8, 7, 4, 4, 2, 7, 2, 5, 1, 1, 4, 2, 4, 7, 1, -1, 0]

cp's OEIS Frontend

A308778 Central element(s) in the period of the continued fraction expansion of sqrt(n), or 0 if no such element exists, or -1 if n is a square.

Table of values

List of values

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

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

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