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 | 2 |
| 2 | 24 |
| 3 | 500 |
| 4 | 13720 |
| 5 | 444528 |
| 6 | 16099776 |
| 7 | 631628712 |
| 8 | 26317863000 |
| 9 | 1149330319280 |
| 10 | 52120705189696 |
| 11 | 2437827529099872 |
| 12 | 117006104720150464 |
| 13 | 5740095404246000000 |
| 14 | 286939169121965760000 |
| 15 | 14579498741074214418000 |