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 | 44 |
| 2 | 45 |
| 3 | 20 |
| 4 | 10 |
| 5 | 0 |
| 6 | 1 |
| 7 | 440192 |
| 8 | 975360 |
| 9 | 1035680 |
| 10 | 696320 |
| 11 | 329600 |
| 12 | 114176 |
| 13 | 31040 |
| 14 | 5120 |
| 15 | 1280 |
| 16 | 0 |
| 17 | 32 |
| 18 | 52097831424 |
| 19 | 179811290880 |
| 20 | 298276007040 |
| 21 | 315423836640 |
| 22 | 237742646400 |
| 23 | 135296008128 |
| 24 | 60059024640 |