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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 9 |
| 5 | 20 |
| 6 | 279 |
| 7 | 512 |
| 8 | 19087 |
| 9 | 71602 |
| 10 | 636365 |
| 11 | 1517042 |
| 12 | 321965982 |
| 13 | 240609602 |
| 14 | 8809543877 |
| 15 | 144729615032 |
| 16 | 26818608209252 |
| 17 | 6603755558402 |
| 18 | 2737593592637477 |