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 | 3 |
| 2 | 14 |
| 3 | 98 |
| 4 | 920 |
| 5 | 10792 |
| 6 | 151888 |
| 7 | 2494032 |
| 8 | 46803072 |
| 9 | 988095104 |
| 10 | 23178247424 |
| 11 | 598074306304 |
| 12 | 16835199087616 |
| 13 | 513385352524800 |
| 14 | 16859837094942720 |
| 15 | 593234633904293888 |
| 16 | 22265289445252628480 |
| 17 | 887889931920920313856 |
| 18 | 37489832605652634763264 |
| 19 | 1670894259596134872711168 |