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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 24 |
| 5 | 204 |
| 6 | 1024 |
| 7 | 3628 |
| 8 | 10320 |
| 9 | 25096 |
| 10 | 54400 |
| 11 | 107880 |
| 12 | 199400 |
| 13 | 348020 |
| 14 | 579264 |
| 15 | 926324 |
| 16 | 1431584 |
| 17 | 2148048 |
| 18 | 3141120 |
| 19 | 4490256 |
| 20 | 6291000 |
| 21 | 8656860 |
| 22 | 11721600 |
| 23 | 15641340 |
| 24 | 20597104 |
| 25 | 26797144 |
| 26 | 34479744 |
| 27 | 43915768 |
| 28 | 55411720 |
| 29 | 69312516 |
| 30 | 86004800 |
| 31 | 105919940 |