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 | 720 |
| 2 | 3600 |
| 3 | 12000 |
| 4 | 40000 |
| 5 | 105000 |
| 6 | 275625 |
| 7 | 617400 |
| 8 | 1382976 |
| 9 | 2765952 |
| 10 | 5531904 |
| 11 | 10160640 |
| 12 | 18662400 |
| 13 | 32076000 |
| 14 | 55130625 |
| 15 | 89842500 |
| 16 | 146410000 |
| 17 | 228399600 |
| 18 | 356303376 |
| 19 | 535927392 |
| 20 | 806105664 |
| 21 | 1175570760 |
| 22 | 1714374025 |
| 23 | 2434614000 |