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 | 6 |
| 2 | 48 |
| 3 | 408 |
| 4 | 3600 |
| 5 | 42336 |
| 6 | 781728 |
| 7 | 13646016 |
| 8 | 90893568 |
| 9 | -1798204416 |
| 10 | 70794720768 |
| 11 | 7538546211840 |
| 12 | 63813109782528 |
| 13 | -12977417912045568 |
| 14 | -320549902414196736 |
| 15 | 33016479733605777408 |
| 16 | 1709506241695601983488 |