A238694 - cp's OEIS frontend

A238694 Smallest k such that 2^n - k and k*2^n - 1 are both prime or 0 if no such k exists.

n	a(n)
1	0
2	1
3	1
4	3
5	1
6	3
7	1
8	5
9	25
10	5
11	31
12	5
13	1
14	15
15	49
16	17
17	1
18	5
19	1
20	17
21	9
22	33
23	69
24	89
25	61
26	111
27	199
28	309
29	75
30	297
31	1
32	5
33	49
34	131
35	31
36	17
37	31
38	131
39	165
40	437
41	55
42	33
43	309
44	495
45	361
46	437
47	999
48	89
49	139
50	195
51	129
52	183
53	685
54	315
55	915
56	189
57	585
58	1035
59	931
60	93
61	1
62	57
63	165

[0, 1, 1, 3, 1, 3, 1, 5, 25, 5, 31, 5, 1, 15, 49, 17, 1, 5, 1, 17, 9, 33, 69, 89, 61, 111, 199, 309, 75, 297, 1, 5, 49, 131, 31, 17, 31, 131, 165, 437, 55, 33, 309, 495, 361, 437, 999, 89, 139, 195, 129, 183, 685, 315, 915, 189, 585, 1035, 931, 93, 1, 57, 165]

cp's OEIS Frontend

A238694 Smallest k such that 2^n - k and k*2^n - 1 are both prime or 0 if no such k exists.

Table of values

List of values