A235709 - cp's OEIS frontend

A235709 Least prime p < prime(n) with 2^p - 1 a quadratic residue modulo prime(n), or 0 if such a number does not exist.

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

[0, 0, 0, 0, 2, 2, 7, 3, 2, 3, 3, 2, 5, 5, 2, 3, 2, 2, 7, 2, 2, 5, 2, 23, 2, 5, 3, 2, 2, 3, 5, 2, 3, 3, 3, 5, 2, 11, 2, 5, 2, 2, 2, 2, 3, 3, 11, 3, 2, 2, 3, 2, 2, 2, 5, 2, 7, 3, 2, 3, 3, 5, 3, 2, 2, 3, 5, 2, 2, 2, 7, 2, 3, 2, 7, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 2, 3, 2, 11, 5, 2, 2, 5, 2, 5, 2, 7, 5, 3, 2]

cp's OEIS Frontend

A235709 Least prime p < prime(n) with 2^p - 1 a quadratic residue modulo prime(n), or 0 if such a number does not exist.

Table of values

List of values

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

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

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