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 | 6 |
| 2 | 84 |
| 3 | 1680 |
| 4 | 39240 |
| 5 | 999216 |
| 6 | 26899896 |
| 7 | 752939424 |
| 8 | 21691531800 |
| 9 | 638947312080 |
| 10 | 19155738105504 |
| 11 | 582589712312064 |
| 12 | 17930566188602136 |
| 13 | 557417298916695600 |
| 14 | 17477836958370383280 |
| 15 | 552090876791399769600 |
| 16 | 17552554240486710112920 |
| 17 | 561230779055361080132880 |