A181692 - cp's OEIS frontend

A181692 The smallest positive m such that 2^m-2^n-1 is prime, or 0 if such an m does not exist.

n	a(n)
0	2
1	3
2	3
3	4
4	6
5	6
6	8
7	8
8	14
9	12
10	14
11	13
12	20
13	14
14	18
15	24
16	22
17	18
18	20
19	20
20	38
21	24
22	42
23	28
24	32
25	32
26	50
27	59
28	34
29	32
30	44
31	32
32	38
33	38
34	36
35	40
36	48
37	42
38	40
39	45
40	48
41	45
42	56
43	45
44	54
45	48
46	76
47	52
48	68
49	66
50	100
51	89
52	80
53	74
54	80
55	57
56	66
57	78
58	98
59	83
60	162
61	62
62	166
63	77
64	66
65	77
66	72
67	76
68	74
69	153
70	80
71	89
72	86
73	77
74	94
75	83
76	78
77	88
78	110
79	115
80	84

[2, 3, 3, 4, 6, 6, 8, 8, 14, 12, 14, 13, 20, 14, 18, 24, 22, 18, 20, 20, 38, 24, 42, 28, 32, 32, 50, 59, 34, 32, 44, 32, 38, 38, 36, 40, 48, 42, 40, 45, 48, 45, 56, 45, 54, 48, 76, 52, 68, 66, 100, 89, 80, 74, 80, 57, 66, 78, 98, 83, 162, 62, 166, 77, 66, 77, 72, 76, 74, 153, 80, 89, 86, 77, 94, 83, 78, 88, 110, 115, 84]

cp's OEIS Frontend

A181692 The smallest positive m such that 2^m-2^n-1 is prime, or 0 if such an m does not exist.

Table of values

List of values

n	a(n)
0	2
1	3
2	3
3	4
4	6
5	6
6	8
7	8
8	14
9	12
10	14
11	13
12	20
13	14
14	18
15	24
16	22
17	18
18	20
19	20
20	38
21	24
22	42
23	28
24	32
25	32
26	50
27	59
28	34
29	32
30	44
31	32
32	38
33	38
34	36
35	40
36	48
37	42
38	40
39	45
40	48
41	45
42	56
43	45
44	54
45	48
46	76
47	52
48	68
49	66
50	100
51	89
52	80
53	74
54	80
55	57
56	66
57	78
58	98
59	83
60	162
61	62
62	166
63	77
64	66
65	77
66	72
67	76
68	74
69	153
70	80
71	89
72	86
73	77
74	94
75	83
76	78
77	88
78	110
79	115
80	84

n	a(n)
0	2
1	3
2	3
3	4
4	6
5	6
6	8
7	8
8	14
9	12
10	14
11	13
12	20
13	14
14	18
15	24
16	22
17	18
18	20
19	20
20	38
21	24
22	42
23	28
24	32
25	32
26	50
27	59
28	34
29	32
30	44
31	32
32	38
33	38
34	36
35	40
36	48
37	42
38	40
39	45
40	48
41	45
42	56
43	45
44	54
45	48
46	76
47	52
48	68
49	66
50	100
51	89
52	80
53	74
54	80
55	57
56	66
57	78
58	98
59	83
60	162
61	62
62	166
63	77
64	66
65	77
66	72
67	76
68	74
69	153
70	80
71	89
72	86
73	77
74	94
75	83
76	78
77	88
78	110
79	115
80	84

n	a(n)
0	2
1	3
2	3
3	4
4	6
5	6
6	8
7	8
8	14
9	12
10	14
11	13
12	20
13	14
14	18
15	24
16	22
17	18
18	20
19	20
20	38
21	24
22	42
23	28
24	32
25	32
26	50
27	59
28	34
29	32
30	44
31	32
32	38
33	38
34	36
35	40
36	48
37	42
38	40
39	45
40	48
41	45
42	56
43	45
44	54
45	48
46	76
47	52
48	68
49	66
50	100
51	89
52	80
53	74
54	80
55	57
56	66
57	78
58	98
59	83
60	162
61	62
62	166
63	77
64	66
65	77
66	72
67	76
68	74
69	153
70	80
71	89
72	86
73	77
74	94
75	83
76	78
77	88
78	110
79	115
80	84