A235712 - cp's OEIS frontend

A235712 Least prime p < prime(n) with 2^p + 1 a quadratic nonresidue modulo prime(n), or 0 if such a prime p does not exist.

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

[0, 2, 0, 2, 7, 2, 2, 5, 2, 11, 11, 2, 7, 2, 2, 2, 5, 5, 2, 5, 2, 5, 2, 5, 2, 7, 2, 2, 5, 2, 2, 13, 2, 5, 13, 5, 2, 2, 2, 2, 5, 11, 5, 2, 2, 7, 5, 2, 2, 23, 2, 7, 5, 5, 2, 2, 5, 5, 2, 7, 2, 2, 2, 5, 2, 2, 7, 2, 2, 5, 2, 7, 2, 2, 11, 2, 5, 2, 5, 5, 5, 7, 7, 2, 5, 2, 5, 2, 7, 2, 2, 7, 2, 13, 7, 2, 5, 5, 2, 5]

cp's OEIS Frontend

A235712 Least prime p < prime(n) with 2^p + 1 a quadratic nonresidue modulo prime(n), or 0 if such a prime p does not exist.

Table of values

List of values

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

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

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