A238900 - cp's OEIS frontend

A238900 Least k such that one of 2^n +- 2^k +- 1 is prime, where 0 < k < n, or 0 if there is no such prime.

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

[1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 12, 2, 11, 1, 1, 1, 1, 2, 3, 9, 5, 2, 3, 3, 3, 4, 5, 4, 8, 3, 7, 4, 2, 6, 17, 14, 6, 12, 2, 5, 1, 2, 3, 6, 11, 5, 1, 16, 8, 8, 20, 2, 1, 5, 7, 19, 6, 4, 19, 8, 5, 4, 5, 3, 9, 6, 4, 3, 13, 1, 24]

cp's OEIS Frontend

A238900 Least k such that one of 2^n +- 2^k +- 1 is prime, where 0 < k < n, or 0 if there is no such prime.

Table of values

List of values

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

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

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