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 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 2 |
| 8 | 2 |
| 9 | 6 |
| 10 | 48 |
| 11 | 48 |
| 12 | 48 |
| 13 | 48 |
| 14 | 1536 |
| 15 | 207360 |
| 16 | 207360 |
| 17 | 207360 |
| 18 | 1105920 |
| 19 | 1105920 |
| 20 | 17694720 |
| 21 | 30098718720 |
| 22 | 15410543984640 |
| 23 | 15410543984640 |
| 24 | 481579499520 |
| 25 | 60197437440000 |
| 26 | 123284351877120000 |
| 27 | 29958097506140160000 |