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 | 1 |
| 2 | 4 |
| 3 | 36 |
| 4 | 484 |
| 5 | 8840 |
| 6 | 203868 |
| 7 | 5691308 |
| 8 | 186612592 |
| 9 | 7031373264 |
| 10 | 299397454080 |
| 11 | 14218443479328 |
| 12 | 745142534904480 |
| 13 | 42717896158340832 |
| 14 | 2659373970144454080 |
| 15 | 178666030775042040000 |
| 16 | 12884568940594969258752 |
| 17 | 992750028716940749121792 |