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 | 16 |
| 2 | 6746 |
| 3 | 313464 |
| 4 | 9479292 |
| 5 | 174763208 |
| 6 | 2262089361 |
| 7 | 22088730348 |
| 8 | 171764779170 |
| 9 | 1106667645872 |
| 10 | 6087616677864 |
| 11 | 29267369636800 |
| 12 | 125299076209408 |
| 13 | 485013257865472 |
| 14 | 1718947213795328 |
| 15 | 5636819806209792 |
| 16 | 17235204961273600 |
| 17 | 49467590616190208 |
| 18 | 134058587073795072 |
| 19 | 344809293460572928 |
| 20 | 845577589114049792 |
| 21 | 1985060631106310400 |