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 | 0 |
| 2 | 0 |
| 3 | 261120 |
| 4 | 18947520 |
| 5 | 535818240 |
| 6 | 8320327680 |
| 7 | 83347937280 |
| 8 | 622558664640 |
| 9 | 3614759362560 |
| 10 | 17694184734720 |
| 11 | 73337844372480 |
| 12 | 272615629589760 |
| 13 | 898646461378560 |
| 14 | 2752654757806080 |
| 15 | 7687895624386560 |