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 | 0 |
| 5 | 0 |
| 6 | 12 |
| 7 | 352 |
| 8 | 5392 |
| 9 | 59670 |
| 10 | 541044 |
| 11 | 4285127 |
| 12 | 30772896 |
| 13 | 205200710 |
| 14 | 1291195620 |
| 15 | 7754735430 |
| 16 | 44827592160 |
| 17 | 251003101440 |
| 18 | 1368033658992 |
| 19 | 7285815623268 |
| 20 | 38033923266368 |
| 21 | 195107105534280 |
| 22 | 985573624414808 |
| 23 | 4911044001390648 |