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 | 0 |
| 2 | 4 |
| 3 | 162 |
| 4 | 23328 |
| 5 | 9072000 |
| 6 | 7873200000 |
| 7 | 13367512620000 |
| 8 | 40367907740160000 |
| 9 | 201793403949096960000 |
| 10 | 1578804075215377920000000 |
| 11 | 18484433452834116768000000000 |
| 12 | 312162837144268369009766400000000 |
| 13 | 7374810540967959718955457331200000000 |