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) |
|---|---|
| 1 | 3 |
| 2 | 12 |
| 3 | 234 |
| 4 | 1080 |
| 5 | 6048 |
| 6 | 6552 |
| 7 | 435708 |
| 8 | 4713984 |
| 9 | 18506880 |
| 10 | 36197280 |
| 11 | 275890944 |
| 12 | 299980800 |
| 13 | 4138364160 |
| 14 | 13286744064 |
| 15 | 17827568640 |
| 16 | 30600708096 |
| 17 | 459010621440 |
| 18 | 2198278051200 |
| 19 | 2567400675840 |
| 20 | 3321402084000 |
| 21 | 4959751305600 |
| 22 | 295185198672000 |
| 23 | 1217745604232064 |