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 | 9 |
| 3 | 170 |
| 4 | 3059 |
| 5 | 54900 |
| 6 | 985149 |
| 7 | 17677790 |
| 8 | 317215079 |
| 9 | 5692193640 |
| 10 | 102142270449 |
| 11 | 1832868674450 |
| 12 | 32889493869659 |
| 13 | 590178020979420 |
| 14 | 10590314883759909 |
| 15 | 190035489886698950 |
| 16 | 3410048503076821199 |
| 17 | 61190837565496082640 |
| 18 | 1098025027675852666329 |
| 19 | 19703259660599851911290 |