A377365 - cp's OEIS frontend

A377365 a(n) = least k such that 2n*5^k+1 is prime, or 0 if no prime is reached.

n	a(n)
1	1
2	2
3	1
4	1
5	2
6	1
7	1
8	2
9	3
10	1
11	4
12	2
13	1
14	2
15	1
16	3
17	8
18	1
19	1
20	1036
21	1
22	3
23	2
24	1
25	1
26	2
27	1
28	1
29	2
30	4
31	1
32	2
33	1
34	3
35	6
36	2
37	257
38	2
39	2
40	1
41	40
42	1
43	1
44	4
45	2
46	1
47	2
48	10
49	1
50	4
51	2
52	1
53	6
54	1
55	3
56	2
57	1
58	15
59	4
60	1
61	79
62	48
63	1
64	1
65	2
66	1
67	5
68	6
69	1
70	1
71	6
72	4
73	3
74	2
75	1
76	1
77	2
78	3
79	3
80	2
81	1
82	1
83	6

[1, 2, 1, 1, 2, 1, 1, 2, 3, 1, 4, 2, 1, 2, 1, 3, 8, 1, 1, 1036, 1, 3, 2, 1, 1, 2, 1, 1, 2, 4, 1, 2, 1, 3, 6, 2, 257, 2, 2, 1, 40, 1, 1, 4, 2, 1, 2, 10, 1, 4, 2, 1, 6, 1, 3, 2, 1, 15, 4, 1, 79, 48, 1, 1, 2, 1, 5, 6, 1, 1, 6, 4, 3, 2, 1, 1, 2, 3, 3, 2, 1, 1, 6]

cp's OEIS Frontend

A377365 a(n) = least k such that 2n*5^k+1 is prime, or 0 if no prime is reached.

Table of values

List of values