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 | 2 |
| 2 | 8 |
| 3 | 56 |
| 4 | 726 |
| 5 | 17938 |
| 6 | 722680 |
| 7 | 35955180 |
| 8 | 1798971434 |
| 9 | 83885891894 |
| 10 | 3612380896332 |
| 11 | 145277787750064 |
| 12 | 5534505187364062 |
| 13 | 202229611397865690 |
| 14 | 7158136006402746464 |
| 15 | 247316732670273773108 |
| 16 | 8389241054998193347410 |