A387331 - cp's OEIS frontend

A387331 Least k such that n*k + 1 is a prime > 2 with 2 as a primitive root; a(n) = 0 if no such k exists.

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

[2, 1, 4, 1, 2, 2, 4, 0, 2, 1, 6, 1, 4, 2, 4, 0, 26, 1, 22, 3, 10, 3, 6, 0, 4, 2, 6, 1, 2, 2, 12, 0, 2, 13, 6, 1, 4, 11, 14, 0, 2, 5, 4, 15, 4, 3, 14, 0, 4, 2, 12, 1, 2, 3, 12, 0, 26, 1, 12, 1, 58, 6, 6, 0, 2, 1, 4, 9, 2, 3, 12, 0, 4, 2, 38, 25, 50, 7, 4, 0, 2]

cp's OEIS Frontend

A387331 Least k such that n*k + 1 is a prime > 2 with 2 as a primitive root; a(n) = 0 if no such k exists.

Table of values

List of values

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

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

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