A242195 - cp's OEIS frontend

A242195 Least prime divisor of the n-th tangent number T_n which does not divide any T_k with k < n, or 1 if such a primitive prime divisor of T_n does not exist.

n	a(n)
1	1
2	2
3	1
4	17
5	31
6	691
7	43
8	257
9	73
10	41
11	89
12	103
13	2731
14	113
15	151
16	37
17	43691
18	109
19	174763
20	61681
21	337
22	59
23	178481
24	97
25	251
26	157
27	39409
28	113161
29	67
30	1321
31	266689
32	641
33	839
34	101
35	281
36	433
37	223
38	229
39	121369
40	631

[1, 2, 1, 17, 31, 691, 43, 257, 73, 41, 89, 103, 2731, 113, 151, 37, 43691, 109, 174763, 61681, 337, 59, 178481, 97, 251, 157, 39409, 113161, 67, 1321, 266689, 641, 839, 101, 281, 433, 223, 229, 121369, 631]

cp's OEIS Frontend

A242195 Least prime divisor of the n-th tangent number T_n which does not divide any T_k with k < n, or 1 if such a primitive prime divisor of T_n does not exist.

Table of values

List of values