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 | 0 |
| 4 | 196848 |
| 5 | 24576 |
| 6 | 17356032 |
| 7 | 6782976 |
| 8 | 448438518 |
| 9 | 274735104 |
| 10 | 5823343872 |
| 11 | 4366565376 |
| 12 | 48362165472 |
| 13 | 39912726528 |
| 14 | 292010062848 |
| 15 | 253343072256 |
| 16 | 1393763244336 |
| 17 | 1241347399680 |
| 18 | 5550621292032 |
| 19 | 5010361122816 |