A358016 - cp's OEIS frontend

A358016 a(n) is the largest k <= n-2 such that k^2 == 1 (mod n).

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

[1, 1, 1, 1, 1, 5, 1, 1, 1, 7, 1, 1, 11, 9, 1, 1, 1, 11, 13, 1, 1, 19, 1, 1, 1, 15, 1, 19, 1, 17, 23, 1, 29, 19, 1, 1, 25, 31, 1, 29, 1, 23, 26, 1, 1, 41, 1, 1, 35, 27, 1, 1, 34, 43, 37, 1, 1, 49, 1, 1, 55, 33, 51, 43, 1, 35, 47, 41, 1, 55, 1, 1, 49, 39, 43, 53]

cp's OEIS Frontend

A358016 a(n) is the largest k <= n-2 such that k^2 == 1 (mod n).

Table of values

List of values

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

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

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