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 | 1 |
| 3 | 5 |
| 4 | 56 |
| 5 | 1092 |
| 6 | 32670 |
| 7 | 1387815 |
| 8 | 79389310 |
| 9 | 5882844968 |
| 10 | 548129834616 |
| 11 | 62720089624920 |
| 12 | 8646340208462880 |
| 13 | 1413380381699497200 |
| 14 | 270316008395632253340 |
| 15 | 59800308109377016336155 |
| 16 | 15151722444639718679892150 |
| 17 | 4359147487054262623576455600 |