A127587 - cp's OEIS frontend

A127587 Smallest nonnegative integer k such that (k+1)*2^n-1 is prime.

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

[2, 1, 0, 0, 1, 0, 1, 0, 4, 6, 4, 2, 1, 0, 4, 3, 1, 0, 1, 0, 13, 6, 25, 12, 38, 21, 10, 15, 7, 3, 1, 0, 4, 5, 2, 23, 11, 5, 2, 24, 23, 11, 5, 2, 13, 6, 19, 9, 4, 18, 10, 20, 19, 9, 4, 2, 31, 15, 7, 3, 1, 0, 11, 5, 2, 66, 62, 42, 62, 39, 19, 9, 4, 14, 11, 5, 2, 54, 46, 29, 14, 29, 14, 63, 31, 15, 7]

cp's OEIS Frontend

A127587 Smallest nonnegative integer k such that (k+1)*2^n-1 is prime.

Table of values

List of values

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

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

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