A108234 - cp's OEIS frontend

A108234 Minimum m such that n*2^m+k is prime, for k < 2^m. In other words, assuming you've read n out of a binary stream, a(n) is the minimum number of additional bits (appended to the least significant end of n) you must read before it is possible to obtain a prime.

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

[1, 0, 0, 2, 0, 1, 0, 1, 1, 2, 0, 3, 0, 1, 1, 2, 0, 1, 0, 1, 1, 2, 0, 2, 2, 1, 2, 2, 0, 1, 0, 2, 1, 2, 1, 1, 0, 3, 1, 2, 0, 3, 0, 1, 2, 3, 0, 1, 2, 1, 1, 2, 0, 1, 2, 1, 2, 2, 0, 2, 0, 2, 1, 2, 1, 4, 0, 1, 1, 2, 0, 3, 0, 1, 1, 2, 2, 1, 0, 3, 1, 2, 0, 2, 3, 1, 2, 2, 0, 1, 2, 3, 2, 2, 1, 1, 0, 1, 1, 2]

cp's OEIS Frontend

A108234 Minimum m such that n*2^m+k is prime, for k < 2^m. In other words, assuming you've read n out of a binary stream, a(n) is the minimum number of additional bits (appended to the least significant end of n) you must read before it is possible to obtain a prime.

Table of values

List of values

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

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

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