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 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 35 |
| 5 | 1411 |
| 6 | 1130531 |
| 7 | 12198455835 |
| 8 | 2697818331680661 |
| 9 | 15224734061438247321497 |
| 10 | 2750892211809150446995735533513 |
| 11 | 19464657391668924966791023043937578299025 |