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 | 45 |
| 2 | 1350 |
| 3 | 34650 |
| 4 | 831600 |
| 5 | 19459440 |
| 6 | 454053600 |
| 7 | 10702692000 |
| 8 | 256864608000 |
| 9 | 6307453152000 |
| 10 | 158947819430400 |
| 11 | 4118193503424000 |
| 12 | 109818493424640000 |
| 13 | 3015784780968960000 |
| 14 | 85303626661693440000 |