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 | 19 |
| 3 | 540 |
| 4 | 23597 |
| 5 | 1381695 |
| 6 | 101682724 |
| 7 | 9016296289 |
| 8 | 935625630797 |
| 9 | 111226656560877 |
| 10 | 14903545528332565 |
| 11 | 2222230881719482634 |
| 12 | 364942065096639623872 |
| 13 | 65448490334085989020670 |
| 14 | 12726830901257817750060165 |
| 15 | 2667188536603107740647377075 |
| 16 | 599286881811684624273478547325 |