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 | 48 |
| 3 | 1704 |
| 4 | 71490 |
| 5 | 3291780 |
| 6 | 160844160 |
| 7 | 8189867280 |
| 8 | 429832053840 |
| 9 | 23088359467040 |
| 10 | 1263134996327680 |
| 11 | 70138971602098560 |
| 12 | 3942799810867610280 |
| 13 | 223942062435751452240 |
| 14 | 12831882367225056387840 |
| 15 | 740872398293620831990080 |