A087780 - cp's OEIS frontend

A087780 Number of non-congruent solutions to x^2 == 2 mod n.

n	a(n)
1	1
2	1
3	0
4	0
5	0
6	0
7	2
8	0
9	0
10	0
11	0
12	0
13	0
14	2
15	0
16	0
17	2
18	0
19	0
20	0
21	0
22	0
23	2
24	0
25	0
26	0
27	0
28	0
29	0
30	0
31	2
32	0
33	0
34	2
35	0
36	0
37	0
38	0
39	0
40	0
41	2
42	0
43	0
44	0
45	0
46	2
47	2
48	0
49	2
50	0
51	0
52	0
53	0
54	0
55	0
56	0
57	0
58	0
59	0
60	0
61	0
62	2
63	0
64	0
65	0
66	0
67	0
68	0
69	0
70	0
71	2
72	0
73	2
74	0
75	0
76	0
77	0
78	0
79	2
80	0
81	0
82	2
83	0
84	0
85	0
86	0
87	0
88	0
89	2
90	0
91	0
92	0
93	0
94	2
95	0
96	0
97	2
98	2
99	0
100	0
101	0
102	0
103	2
104	0
105	0

[1, 1, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 2, 0, 0, 2, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 2, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 2, 2, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 2, 0, 0, 0, 0, 0, 2, 0, 0, 2, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 2, 2, 0, 0, 0, 0, 2, 0, 0]

cp's OEIS Frontend

A087780 Number of non-congruent solutions to x^2 == 2 mod n.

Table of values

List of values

n	a(n)
1	1
2	1
3	0
4	0
5	0
6	0
7	2
8	0
9	0
10	0
11	0
12	0
13	0
14	2
15	0
16	0
17	2
18	0
19	0
20	0
21	0
22	0
23	2
24	0
25	0
26	0
27	0
28	0
29	0
30	0
31	2
32	0
33	0
34	2
35	0
36	0
37	0
38	0
39	0
40	0
41	2
42	0
43	0
44	0
45	0
46	2
47	2
48	0
49	2
50	0
51	0
52	0
53	0
54	0
55	0
56	0
57	0
58	0
59	0
60	0
61	0
62	2
63	0
64	0
65	0
66	0
67	0
68	0
69	0
70	0
71	2
72	0
73	2
74	0
75	0
76	0
77	0
78	0
79	2
80	0
81	0
82	2
83	0
84	0
85	0
86	0
87	0
88	0
89	2
90	0
91	0
92	0
93	0
94	2
95	0
96	0
97	2
98	2
99	0
100	0
101	0
102	0
103	2
104	0
105	0

n	a(n)
1	1
2	1
3	0
4	0
5	0
6	0
7	2
8	0
9	0
10	0
11	0
12	0
13	0
14	2
15	0
16	0
17	2
18	0
19	0
20	0
21	0
22	0
23	2
24	0
25	0
26	0
27	0
28	0
29	0
30	0
31	2
32	0
33	0
34	2
35	0
36	0
37	0
38	0
39	0
40	0
41	2
42	0
43	0
44	0
45	0
46	2
47	2
48	0
49	2
50	0
51	0
52	0
53	0
54	0
55	0
56	0
57	0
58	0
59	0
60	0
61	0
62	2
63	0
64	0
65	0
66	0
67	0
68	0
69	0
70	0
71	2
72	0
73	2
74	0
75	0
76	0
77	0
78	0
79	2
80	0
81	0
82	2
83	0
84	0
85	0
86	0
87	0
88	0
89	2
90	0
91	0
92	0
93	0
94	2
95	0
96	0
97	2
98	2
99	0
100	0
101	0
102	0
103	2
104	0
105	0

n	a(n)
1	1
2	1
3	0
4	0
5	0
6	0
7	2
8	0
9	0
10	0
11	0
12	0
13	0
14	2
15	0
16	0
17	2
18	0
19	0
20	0
21	0
22	0
23	2
24	0
25	0
26	0
27	0
28	0
29	0
30	0
31	2
32	0
33	0
34	2
35	0
36	0
37	0
38	0
39	0
40	0
41	2
42	0
43	0
44	0
45	0
46	2
47	2
48	0
49	2
50	0
51	0
52	0
53	0
54	0
55	0
56	0
57	0
58	0
59	0
60	0
61	0
62	2
63	0
64	0
65	0
66	0
67	0
68	0
69	0
70	0
71	2
72	0
73	2
74	0
75	0
76	0
77	0
78	0
79	2
80	0
81	0
82	2
83	0
84	0
85	0
86	0
87	0
88	0
89	2
90	0
91	0
92	0
93	0
94	2
95	0
96	0
97	2
98	2
99	0
100	0
101	0
102	0
103	2
104	0
105	0