A231725 - cp's OEIS frontend

A231725 Least positive integer k < n such that n + k + 2^k is prime, or 0 if such an integer k does not exist.

n	a(n)
1	0
2	1
3	0
4	1
5	2
6	3
7	2
8	1
9	4
10	1
11	2
12	3
13	2
14	1
15	10
16	1
17	2
18	3
19	6
20	1
21	4
22	5
23	2
24	5
25	2
26	1
27	4
28	1
29	8
30	3
31	2
32	3
33	4
34	1
35	2
36	3
37	2
38	1
39	4
40	1
41	2
42	3
43	6
44	1
45	12
46	5
47	2
48	3
49	8
50	1
51	4
52	5
53	2
54	11
55	2
56	1
57	6
58	1
59	4
60	3
61	2
62	3
63	4
64	1
65	2
66	5
67	2
68	1
69	4
70	1
71	22
72	3
73	2
74	57
75	10
76	1
77	2
78	3
79	6
80	1
81	4
82	11
83	2
84	11
85	8
86	1
87	4
88	7
89	4
90	3
91	2
92	3
93	4
94	1
95	2
96	3
97	2
98	1
99	16
100	1

[0, 1, 0, 1, 2, 3, 2, 1, 4, 1, 2, 3, 2, 1, 10, 1, 2, 3, 6, 1, 4, 5, 2, 5, 2, 1, 4, 1, 8, 3, 2, 3, 4, 1, 2, 3, 2, 1, 4, 1, 2, 3, 6, 1, 12, 5, 2, 3, 8, 1, 4, 5, 2, 11, 2, 1, 6, 1, 4, 3, 2, 3, 4, 1, 2, 5, 2, 1, 4, 1, 22, 3, 2, 57, 10, 1, 2, 3, 6, 1, 4, 11, 2, 11, 8, 1, 4, 7, 4, 3, 2, 3, 4, 1, 2, 3, 2, 1, 16, 1]

cp's OEIS Frontend

A231725 Least positive integer k < n such that n + k + 2^k is prime, or 0 if such an integer k does not exist.

Table of values

List of values

n	a(n)
1	0
2	1
3	0
4	1
5	2
6	3
7	2
8	1
9	4
10	1
11	2
12	3
13	2
14	1
15	10
16	1
17	2
18	3
19	6
20	1
21	4
22	5
23	2
24	5
25	2
26	1
27	4
28	1
29	8
30	3
31	2
32	3
33	4
34	1
35	2
36	3
37	2
38	1
39	4
40	1
41	2
42	3
43	6
44	1
45	12
46	5
47	2
48	3
49	8
50	1
51	4
52	5
53	2
54	11
55	2
56	1
57	6
58	1
59	4
60	3
61	2
62	3
63	4
64	1
65	2
66	5
67	2
68	1
69	4
70	1
71	22
72	3
73	2
74	57
75	10
76	1
77	2
78	3
79	6
80	1
81	4
82	11
83	2
84	11
85	8
86	1
87	4
88	7
89	4
90	3
91	2
92	3
93	4
94	1
95	2
96	3
97	2
98	1
99	16
100	1

n	a(n)
1	0
2	1
3	0
4	1
5	2
6	3
7	2
8	1
9	4
10	1
11	2
12	3
13	2
14	1
15	10
16	1
17	2
18	3
19	6
20	1
21	4
22	5
23	2
24	5
25	2
26	1
27	4
28	1
29	8
30	3
31	2
32	3
33	4
34	1
35	2
36	3
37	2
38	1
39	4
40	1
41	2
42	3
43	6
44	1
45	12
46	5
47	2
48	3
49	8
50	1
51	4
52	5
53	2
54	11
55	2
56	1
57	6
58	1
59	4
60	3
61	2
62	3
63	4
64	1
65	2
66	5
67	2
68	1
69	4
70	1
71	22
72	3
73	2
74	57
75	10
76	1
77	2
78	3
79	6
80	1
81	4
82	11
83	2
84	11
85	8
86	1
87	4
88	7
89	4
90	3
91	2
92	3
93	4
94	1
95	2
96	3
97	2
98	1
99	16
100	1

n	a(n)
1	0
2	1
3	0
4	1
5	2
6	3
7	2
8	1
9	4
10	1
11	2
12	3
13	2
14	1
15	10
16	1
17	2
18	3
19	6
20	1
21	4
22	5
23	2
24	5
25	2
26	1
27	4
28	1
29	8
30	3
31	2
32	3
33	4
34	1
35	2
36	3
37	2
38	1
39	4
40	1
41	2
42	3
43	6
44	1
45	12
46	5
47	2
48	3
49	8
50	1
51	4
52	5
53	2
54	11
55	2
56	1
57	6
58	1
59	4
60	3
61	2
62	3
63	4
64	1
65	2
66	5
67	2
68	1
69	4
70	1
71	22
72	3
73	2
74	57
75	10
76	1
77	2
78	3
79	6
80	1
81	4
82	11
83	2
84	11
85	8
86	1
87	4
88	7
89	4
90	3
91	2
92	3
93	4
94	1
95	2
96	3
97	2
98	1
99	16
100	1