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 | 0 |
| 2 | 8 |
| 3 | 12 |
| 4 | 176 |
| 5 | 840 |
| 6 | 7416 |
| 7 | 58800 |
| 8 | 529728 |
| 9 | 5152896 |
| 10 | 54070560 |
| 11 | 612342720 |
| 12 | 7472424384 |
| 13 | 97979207040 |
| 14 | 1375839795456 |
| 15 | 20619488373120 |
| 16 | 328716465177600 |
| 17 | 5556948993792000 |
| 18 | 99324048442208256 |
| 19 | 1871986425192990720 |
| 20 | 37110785352536724480 |
| 21 | 772059856808638218240 |
| 22 | 16820447458491885035520 |