A005420 - cp's OEIS frontend

A005420 Largest prime factor of 2^n - 1.

n	a(n)
2	3
3	7
4	5
5	31
6	7
7	127
8	17
9	73
10	31
11	89
12	13
13	8191
14	127
15	151
16	257
17	131071
18	73
19	524287
20	41
21	337
22	683
23	178481
24	241
25	1801
26	8191
27	262657
28	127
29	2089
30	331
31	2147483647
32	65537
33	599479
34	131071
35	122921
36	109
37	616318177
38	524287
39	121369
40	61681
41	164511353
42	5419

[3, 7, 5, 31, 7, 127, 17, 73, 31, 89, 13, 8191, 127, 151, 257, 131071, 73, 524287, 41, 337, 683, 178481, 241, 1801, 8191, 262657, 127, 2089, 331, 2147483647, 65537, 599479, 131071, 122921, 109, 616318177, 524287, 121369, 61681, 164511353, 5419]

cp's OEIS Frontend

A005420 Largest prime factor of 2^n - 1.

Table of values

List of values