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 | 4 |
| 2 | 28 |
| 3 | 384 |
| 4 | 10496 |
| 5 | 573440 |
| 6 | 62652416 |
| 7 | 13690208256 |
| 8 | 5982889443328 |
| 9 | 5229277301702656 |
| 10 | 9141181343655264256 |
| 11 | 31958984107701798174720 |
| 12 | 223467104335874481157308416 |
| 13 | 3125102257923487167715657908224 |