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 | 1 |
| 1 | 12 |
| 2 | 108 |
| 3 | 848 |
| 4 | 6192 |
| 5 | 43200 |
| 6 | 292224 |
| 7 | 1933056 |
| 8 | 12572928 |
| 9 | 80702464 |
| 10 | 512532480 |
| 11 | 3226742784 |
| 12 | 20166803456 |
| 13 | 125262102528 |
| 14 | 773910872064 |
| 15 | 4759428268032 |
| 16 | 29151365234688 |
| 17 | 177913041518592 |
| 18 | 1082361265782784 |
| 19 | 6565932190138368 |