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 | 0 |
| 3 | 0 |
| 4 | 784 |
| 5 | 40496 |
| 6 | 451104 |
| 7 | 2803552 |
| 8 | 12139552 |
| 9 | 41792672 |
| 10 | 121269248 |
| 11 | 310362944 |
| 12 | 718151344 |
| 13 | 1534460624 |
| 14 | 3067048224 |
| 15 | 5801302304 |
| 16 | 10464095808 |
| 17 | 18125622336 |
| 18 | 30299632896 |
| 19 | 49104515712 |
| 20 | 77410664016 |
| 21 | 119081302128 |
| 22 | 179178580768 |