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) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 195 |
| 4 | 7140 |
| 5 | 396900 |
| 6 | 31185000 |
| 7 | 3291888600 |
| 8 | 449513064000 |
| 9 | 77111922888000 |
| 10 | 16235185926960000 |
| 11 | 4116213602701200000 |
| 12 | 1237059394731800640000 |
| 13 | 434864246413372776000000 |
| 14 | 176784623645708110032000000 |
| 15 | 82297894534015170170160000000 |
| 16 | 43496460979945066988294400000000 |