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 | 18 |
| 2 | 288 |
| 3 | 4800 |
| 4 | 86400 |
| 5 | 1693440 |
| 6 | 36126720 |
| 7 | 836075520 |
| 8 | 20901888000 |
| 9 | 562028544000 |
| 10 | 16186422067200 |
| 11 | 497364605337600 |
| 12 | 16247243774361600 |
| 13 | 562404592189440000 |
| 14 | 20567939371499520000 |
| 15 | 792551263781781504000 |
| 16 | 32098326183162150912000 |
| 17 | 1363234794367239585792000 |