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 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 5 |
| 6 | 144 |
| 7 | 7 |
| 8 | 384 |
| 9 | 162 |
| 10 | 19200 |
| 11 | 11 |
| 12 | 1244160 |
| 13 | 13 |
| 14 | 4515840 |
| 15 | 1458000 |
| 16 | 10321920 |
| 17 | 17 |
| 18 | 75246796800 |
| 19 | 19 |
| 20 | 278691840000 |
| 21 | 1080203040 |
| 22 | 899245670400 |
| 23 | 23 |
| 24 | 16686729658368000 |
| 25 | 375000 |
| 26 | 663152807116800 |
| 27 | 7142567040 |
| 28 | 209964381084057600 |
| 29 | 29 |
| 30 | 1229978843118305280000000 |