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 | 24 |
| 3 | 232 |
| 4 | 3840 |
| 5 | 111904 |
| 6 | 5785344 |
| 7 | 529662592 |
| 8 | 85449338880 |
| 9 | 24204383609344 |
| 10 | 11986829259362304 |
| 11 | 10361640102119729152 |
| 12 | 15589910824599107174400 |
| 13 | 40815393380277274447519744 |
| 14 | 185575767151388880816233447424 |
| 15 | 1465910356757779350231777997914112 |