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) |
|---|---|
| 2 | 0 |
| 3 | 2 |
| 4 | 14 |
| 5 | 80 |
| 6 | 512 |
| 7 | 3776 |
| 8 | 31376 |
| 9 | 290456 |
| 10 | 2970296 |
| 11 | 33276536 |
| 12 | 405440216 |
| 13 | 5338909736 |
| 14 | 75572075816 |
| 15 | 1144441325096 |
| 16 | 18464406889256 |
| 17 | 316212570391976 |
| 18 | 5729159765566376 |