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 | 7 |
| 3 | 81 |
| 4 | 1299 |
| 5 | 26565 |
| 6 | 659655 |
| 7 | 19256265 |
| 8 | 645765435 |
| 9 | 24453391725 |
| 10 | 1031685317775 |
| 11 | 47978413923825 |
| 12 | 2437962646702275 |
| 13 | 134374287343821525 |
| 14 | 7984095179348863575 |
| 15 | 508687013361879977625 |
| 16 | 34593307096333435324875 |
| 17 | 2500919993138258679112125 |
| 18 | 191526329081848509391017375 |