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.
| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 3 |
| 2 | 7 |
| 3 | 23 |
| 4 | 87 |
| 5 | 343 |
| 6 | 1367 |
| 7 | 5463 |
| 8 | 21847 |
| 9 | 87383 |
| 10 | 349527 |
| 11 | 1398103 |
| 12 | 5592407 |
| 13 | 22369623 |
| 14 | 89478487 |
| 15 | 357913943 |
| 16 | 1431655767 |
| 17 | 5726623063 |
| 18 | 22906492247 |
| 19 | 91625968983 |
| 20 | 366503875927 |
| 21 | 1466015503703 |
| 22 | 5864062014807 |
| 23 | 23456248059223 |
| 24 | 93824992236887 |
| 25 | 375299968947543 |