A069568 - cp's OEIS frontend

A069568 a(n) = smallest number m > 0 such that n followed by m 1's yields a prime, or -1 if no such m exists.

n	a(n)
1	1
2	2
3	1
4	1
5	5
6	1
7	1
8	2
9	2
10	1
11	17
12	136
13	1
14	9
15	1
16	3
17	8
18	1
19	1
20	2
21	1
22	3
23	2
24	1
25	1
26	3
27	1
28	1
29	6
30	2
31	1
32	35
33	1
34	6
35	2
36	4
37	-1
38	-1
39	2
40	1
41	2
42	1
43	1
44	3
45	772
46	1
47	3
48	5
49	1
50	2
51	4
52	1
53	9
54	1
55	31
56	18470
57	1
58	3
59	18
60	1
61	4
62	2
63	1
64	1
65	3
66	1
67	210
68	3
69	1
70	1
71	6
72	2
73	7
74	2
75	1
76	1
77	9
78	4
79	3
80	2
81	1
82	1
83	2
84	5
85	6
86	3
87	149
88	1
89	6
90	2
91	1
92	3
93	2
94	1
95	2
96	7
97	1
98	2
99	1
100	10
101	2
102	1
103	1
104	44
105	1
106	1
107	2
108	5
109	1
110	17
111	16
112	3
113	2
114	2
115	1
116	9
117	1
118	1

[1, 2, 1, 1, 5, 1, 1, 2, 2, 1, 17, 136, 1, 9, 1, 3, 8, 1, 1, 2, 1, 3, 2, 1, 1, 3, 1, 1, 6, 2, 1, 35, 1, 6, 2, 4, -1, -1, 2, 1, 2, 1, 1, 3, 772, 1, 3, 5, 1, 2, 4, 1, 9, 1, 31, 18470, 1, 3, 18, 1, 4, 2, 1, 1, 3, 1, 210, 3, 1, 1, 6, 2, 7, 2, 1, 1, 9, 4, 3, 2, 1, 1, 2, 5, 6, 3, 149, 1, 6, 2, 1, 3, 2, 1, 2, 7, 1, 2, 1, 10, 2, 1, 1, 44, 1, 1, 2, 5, 1, 17, 16, 3, 2, 2, 1, 9, 1, 1]

cp's OEIS Frontend

A069568 a(n) = smallest number m > 0 such that n followed by m 1's yields a prime, or -1 if no such m exists.

Table of values

List of values