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 | 1 |
| 2 | 4 |
| 3 | 45 |
| 4 | 568 |
| 5 | 12423 |
| 6 | 473185 |
| 7 | 31446544 |
| 8 | 3669759648 |
| 9 | 753079344538 |
| 10 | 270970785837211 |
| 11 | 171664742070518870 |
| 12 | 191385314222655170098 |