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 | 720 |
| 2 | 179280 |
| 3 | 16954560 |
| 4 | 396974160 |
| 5 | 4632858720 |
| 6 | 34413301440 |
| 7 | 187477879680 |
| 8 | 814940600400 |
| 9 | 2975469665040 |
| 10 | 9486467837280 |
| 11 | 27053330840640 |
| 12 | 70485969919680 |
| 13 | 169930679355360 |
| 14 | 384163875688320 |
| 15 | 820167497170560 |
| 16 | 1668890801059920 |
| 17 | 3249626139960480 |
| 18 | 6096884624994960 |