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 | 2 |
| 2 | 16 |
| 3 | 218 |
| 4 | 4008 |
| 5 | 139307 |
| 6 | 15547072 |
| 7 | 3647921173 |
| 8 | 1302269111985 |
| 9 | 832889881464413 |
| 10 | 1248703703842553735 |
| 11 | 4253189666054817624993 |