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) |
|---|---|
| 1 | 21 |
| 2 | 405 |
| 3 | 9233 |
| 4 | 200376 |
| 5 | 4215579 |
| 6 | 89981627 |
| 7 | 1935133104 |
| 8 | 41520773667 |
| 9 | 888957906061 |
| 10 | 19043081452793 |
| 11 | 408152775865291 |
| 12 | 8747035260806150 |
| 13 | 187430143072289130 |
| 14 | 4016312124315997845 |
| 15 | 86065761676864158937 |