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 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 8 |
| 5 | 5 |
| 6 | 30 |
| 7 | 14 |
| 8 | 112 |
| 9 | 42 |
| 10 | 420 |
| 11 | 132 |
| 12 | 1584 |
| 13 | 429 |
| 14 | 6006 |
| 15 | 1430 |
| 16 | 22880 |
| 17 | 4862 |
| 18 | 87516 |
| 19 | 16796 |
| 20 | 335920 |
| 21 | 58786 |
| 22 | 1293292 |
| 23 | 208012 |
| 24 | 4992288 |
| 25 | 742900 |
| 26 | 19315400 |
| 27 | 2674440 |
| 28 | 74884320 |
| 29 | 9694845 |
| 30 | 290845350 |
| 31 | 35357670 |
| 32 | 1131445440 |
| 33 | 129644790 |
| 34 | 4407922860 |
| 35 | 477638700 |
| 36 | 17194993200 |