A231776 - cp's OEIS frontend

A231776 Least positive integer k <= n with (2^k + k) * n - 1 prime, or 0 if such a number k does not exist.

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

[1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 6, 2, 10, 1, 2, 1, 2, 1, 2, 1, 4, 2, 2, 1, 2, 8, 6, 1, 2, 1, 4, 2, 2, 1, 8, 1, 4, 1, 2, 2, 14, 2, 2, 1, 2, 1, 2, 6, 2, 1, 4, 2, 2, 3, 8, 1, 6, 1, 2, 1, 8, 5, 4, 1, 2, 1, 2, 6, 42, 2, 6, 2, 4, 2, 2, 1, 2, 1, 4, 1, 4, 2, 8, 1, 2, 1, 2, 1, 6, 1, 8, 20, 2, 1, 2, 6, 10, 1, 2, 2]

cp's OEIS Frontend

A231776 Least positive integer k <= n with (2^k + k) * n - 1 prime, or 0 if such a number k does not exist.

Table of values

List of values

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

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

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