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 | 3 |
| 2 | 2 |
| 3 | 140 |
| 4 | 560 |
| 5 | 2160 |
| 6 | 2772 |
| 7 | 2016 |
| 8 | 16830 |
| 9 | 5148 |
| 10 | 20592 |
| 11 | 10640 |
| 12 | 69300 |
| 13 | 31200 |
| 14 | 156240 |
| 15 | 177840 |
| 16 | 288288 |
| 17 | 143520 |
| 18 | 927360 |
| 19 | 1203840 |
| 20 | 752400 |
| 21 | 1242360 |
| 22 | 2702700 |
| 23 | 2948400 |
| 24 | 3996720 |
| 25 | 1884960 |
| 26 | 5896800 |
| 27 | 2692800 |
| 28 | 1244880 |
| 29 | 15800400 |
| 30 | 4586400 |
| 31 | 11060280 |
| 32 | 15301440 |
| 33 | 14414400 |