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 | 0 |
| 3 | 0 |
| 4 | 48 |
| 5 | 480 |
| 6 | 69120 |
| 7 | 967680 |
| 8 | 61931520 |
| 9 | 557383680 |
| 10 | 55738368000 |
| 11 | 613122048000 |
| 12 | 88289574912000 |
| 13 | 1147764473856000 |
| 14 | 224961836875776000 |
| 15 | 3374427553136640000 |