A345698 - cp's OEIS frontend

A345698 Sierpiński 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	0
2	0
3	0
4	1
5	0
6	0
7	1
8	0
9	0
10	1
11	0
12	2
13	1
14	0
15	0
16	3
17	8
18	0
19	1
20	0
21	0
22	3
23	0
24	1
25	1
26	0
27	1
28	1
29	0
30	0
31	1
32	2
33	0
34	3
35	0
36	0
37	257
38	2
39	0
40	1
41	0
42	1
43	1
44	0
45	2
46	1
47	2
48	0
49	1
50	0
51	0
52	1
53	0
54	0
55	3
56	0
57	1
58	15
59	4
60	1
61	79
62	48
63	0
64	1
65	0
66	1
67	5
68	0
69	0
70	1
71	6
72	4
73	3
74	0
75	0
76	1
77	2
78	0
79	3
80	2
81	0
82	1
83	0
84	2
85	7

[0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 2, 1, 0, 0, 3, 8, 0, 1, 0, 0, 3, 0, 1, 1, 0, 1, 1, 0, 0, 1, 2, 0, 3, 0, 0, 257, 2, 0, 1, 0, 1, 1, 0, 2, 1, 2, 0, 1, 0, 0, 1, 0, 0, 3, 0, 1, 15, 4, 1, 79, 48, 0, 1, 0, 1, 5, 0, 0, 1, 6, 4, 3, 0, 0, 1, 2, 0, 3, 2, 0, 1, 0, 2, 7]

cp's OEIS Frontend

A345698 Sierpiński 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

n	a(n)
1	0
2	0
3	0
4	1
5	0
6	0
7	1
8	0
9	0
10	1
11	0
12	2
13	1
14	0
15	0
16	3
17	8
18	0
19	1
20	0
21	0
22	3
23	0
24	1
25	1
26	0
27	1
28	1
29	0
30	0
31	1
32	2
33	0
34	3
35	0
36	0
37	257
38	2
39	0
40	1
41	0
42	1
43	1
44	0
45	2
46	1
47	2
48	0
49	1
50	0
51	0
52	1
53	0
54	0
55	3
56	0
57	1
58	15
59	4
60	1
61	79
62	48
63	0
64	1
65	0
66	1
67	5
68	0
69	0
70	1
71	6
72	4
73	3
74	0
75	0
76	1
77	2
78	0
79	3
80	2
81	0
82	1
83	0
84	2
85	7

n	a(n)
1	0
2	0
3	0
4	1
5	0
6	0
7	1
8	0
9	0
10	1
11	0
12	2
13	1
14	0
15	0
16	3
17	8
18	0
19	1
20	0
21	0
22	3
23	0
24	1
25	1
26	0
27	1
28	1
29	0
30	0
31	1
32	2
33	0
34	3
35	0
36	0
37	257
38	2
39	0
40	1
41	0
42	1
43	1
44	0
45	2
46	1
47	2
48	0
49	1
50	0
51	0
52	1
53	0
54	0
55	3
56	0
57	1
58	15
59	4
60	1
61	79
62	48
63	0
64	1
65	0
66	1
67	5
68	0
69	0
70	1
71	6
72	4
73	3
74	0
75	0
76	1
77	2
78	0
79	3
80	2
81	0
82	1
83	0
84	2
85	7

cp's OEIS Frontend

A345698 Sierpiński 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

A345698 Sierpiński 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	0
2	0
3	0
4	1
5	0
6	0
7	1
8	0
9	0
10	1
11	0
12	2
13	1
14	0
15	0
16	3
17	8
18	0
19	1
20	0
21	0
22	3
23	0
24	1
25	1
26	0
27	1
28	1
29	0
30	0
31	1
32	2
33	0
34	3
35	0
36	0
37	257
38	2
39	0
40	1
41	0
42	1
43	1
44	0
45	2
46	1
47	2
48	0
49	1
50	0
51	0
52	1
53	0
54	0
55	3
56	0
57	1
58	15
59	4
60	1
61	79
62	48
63	0
64	1
65	0
66	1
67	5
68	0
69	0
70	1
71	6
72	4
73	3
74	0
75	0
76	1
77	2
78	0
79	3
80	2
81	0
82	1
83	0
84	2
85	7