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 | 3 |
| 3 | 60 |
| 4 | 10500 |
| 5 | 18522000 |
| 6 | 359400888000 |
| 7 | 81408613942656000 |
| 8 | 224737840779305293440000 |
| 9 | 7812628980363223707442752000000 |
| 10 | 3508978524227146242839564498172672000000 |