cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A138576 Numbers k such that 2^(2*k - 1) - 1 is prime.

Table of values

n a(n)
1 2
2 3
3 4
4 7
5 9
6 10
7 16
8 31
9 45
10 54
11 64
12 261
13 304
14 640
15 1102
16 1141
17 1609
18 2127
19 2212
20 4845
21 4971
22 5607
23 9969
24 10851
25 11605
26 22249
27 43122
28 55252
29 66025
30 108046
31 378420
32 429717
33 628894
34 699135
35 1488111
36 1510689
37 3486297
38 6733459
39 10498006
40 12018292
41 12982476
42 15201229
43 16291329
44 18578334

List of values

[2, 3, 4, 7, 9, 10, 16, 31, 45, 54, 64, 261, 304, 640, 1102, 1141, 1609, 2127, 2212, 4845, 4971, 5607, 9969, 10851, 11605, 22249, 43122, 55252, 66025, 108046, 378420, 429717, 628894, 699135, 1488111, 1510689, 3486297, 6733459, 10498006, 12018292, 12982476, 15201229, 16291329, 18578334]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.