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 | 756 |
| 3 | 4032 |
| 4 | 20412 |
| 5 | 60480 |
| 6 | 139860 |
| 7 | 326592 |
| 8 | 652428 |
| 9 | 1020096 |
| 10 | 2000376 |
| 11 | 3132864 |
| 12 | 4445532 |
| 13 | 7185024 |
| 14 | 10747296 |
| 15 | 13148352 |
| 16 | 21003948 |
| 17 | 27506304 |
| 18 | 33724404 |
| 19 | 48009024 |
| 20 | 64049832 |
| 21 | 70709184 |
| 22 | 102958128 |
| 23 | 124782336 |
| 24 | 142254252 |
| 25 | 189423360 |
| 26 | 237588120 |
| 27 | 248250240 |
| 28 | 344391264 |