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 | 4 |
| 2 | 24 |
| 3 | 104 |
| 4 | 432 |
| 5 | 1536 |
| 6 | 8736 |
| 7 | 22528 |
| 8 | 111456 |
| 9 | 473600 |
| 10 | 1999872 |
| 11 | 5909760 |
| 12 | 38054016 |
| 13 | 89522176 |
| 14 | 462274560 |
| 15 | 2015330304 |
| 16 | 7304603328 |
| 17 | 22907191296 |
| 18 | 166290432000 |
| 19 | 366506672128 |
| 20 | 2220409884672 |
| 21 | 7645340651520 |
| 22 | 29833839544320 |
| 23 | 95821839806976 |
| 24 | 648494317126656 |