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 | 18 |
| 2 | 324 |
| 3 | 5832 |
| 4 | 104976 |
| 5 | 1889568 |
| 6 | 34012224 |
| 7 | 612220032 |
| 8 | 11019960576 |
| 9 | 198359290368 |
| 10 | 3570467226624 |
| 11 | 64268410079232 |
| 12 | 1156831381426176 |
| 13 | 20822964865671168 |
| 14 | 374813367582081024 |
| 15 | 6746640616477458432 |
| 16 | 121439531096594251776 |
| 17 | 2185911559738696531968 |
| 18 | 39346408075296537575424 |
| 19 | 708235345355337676357632 |
| 20 | 12748236216396078174437376 |