A218465 - cp's OEIS frontend

A218465 Least integer b>2n+1 such that the numbers written as [1,3,...,2n-1,2n+1] and [2n+1,2n-1,...,3,1] in base b are both prime.

n	a(n)
1	4
2	6
3	8
4	13
5	54
6	21
7	56
8	141
9	282
10	335
11	132
12	82
13	3752
14	93
15	40
16	5141
17	774
18	204
19	60790
20	27366
21	270
22	31591
23	60
24	247
25	1976
26	4848
27	7112
28	4954
29	62808
30	84
31	17912
32	78441
33	3696
34	8083
35	5754
36	19210
37	21154
38	17973
39	59580

[4, 6, 8, 13, 54, 21, 56, 141, 282, 335, 132, 82, 3752, 93, 40, 5141, 774, 204, 60790, 27366, 270, 31591, 60, 247, 1976, 4848, 7112, 4954, 62808, 84, 17912, 78441, 3696, 8083, 5754, 19210, 21154, 17973, 59580]

cp's OEIS Frontend

A218465 Least integer b>2n+1 such that the numbers written as [1,3,...,2n-1,2n+1] and [2n+1,2n-1,...,3,1] in base b are both prime.

Table of values

List of values