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 | 0 |
| 2 | 1 |
| 3 | 9 |
| 4 | 102 |
| 5 | 1304 |
| 6 | 20784 |
| 7 | 377286 |
| 8 | 7934693 |
| 9 | 186969913 |
| 10 | 4918785791 |
| 11 | 142381832107 |
| 12 | 4506907611825 |
| 13 | 154723950495961 |
| 14 | 5729421493899419 |
| 15 | 227586600129484543 |
| 16 | 9654927881195999544 |
| 17 | 435660032125475809618 |
| 18 | 20836109197604840372979 |
| 19 | 1052865018045922422499409 |