A345403 - cp's OEIS frontend

A345403 Riesel problem in base 5: a(n) is the smallest k >= 0 such that (2n)5^k - 1 is prime, or -1 if no such k exists.

n	a(n)
1	4
2	0
3	0
4	0
5	3
6	0
7	0
8	1
9	0
10	0
11	1
12	0
13	4
14	1
15	0
16	0
17	163
18	1
19	0
20	1
21	0
22	0
23	1
24	0
25	2
26	5
27	0
28	2
29	7
30	0
31	0
32	5
33	5
34	0
35	1
36	0
37	0
38	1
39	1
40	0
41	1
42	0
43	2058
44	1
45	0
46	26
47	5
48	1
49	0
50	1
51	0
52	0
53	3
54	0
55	0
56	3
57	0
58	32
59	17
60	1
61	2
62	1
63	3
64	0
65	3
66	0
67	8
68	21
69	0
70	0
71	1
72	1
73	4
74	1
75	0
76	0
77	1
78	4
79	0
80	7
81	1
82	0
83	1
84	0

[4, 0, 0, 0, 3, 0, 0, 1, 0, 0, 1, 0, 4, 1, 0, 0, 163, 1, 0, 1, 0, 0, 1, 0, 2, 5, 0, 2, 7, 0, 0, 5, 5, 0, 1, 0, 0, 1, 1, 0, 1, 0, 2058, 1, 0, 26, 5, 1, 0, 1, 0, 0, 3, 0, 0, 3, 0, 32, 17, 1, 2, 1, 3, 0, 3, 0, 8, 21, 0, 0, 1, 1, 4, 1, 0, 0, 1, 4, 0, 7, 1, 0, 1, 0]

cp's OEIS Frontend

A345403 Riesel problem in base 5: a(n) is the smallest k >= 0 such that (2n)5^k - 1 is prime, or -1 if no such k exists.

Table of values

List of values

cp's OEIS Frontend

A345403 Riesel problem in base 5: a(n) is the smallest k >= 0 such that (2*n)*5^k - 1 is prime, or -1 if no such k exists.

Table of values

List of values

A345403 Riesel problem in base 5: a(n) is the smallest k >= 0 such that (2n)5^k - 1 is prime, or -1 if no such k exists.