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) |
|---|---|
| 3 | 6 |
| 4 | 36 |
| 5 | 210 |
| 6 | 4560 |
| 7 | 6426 |
| 8 | 326040 |
| 9 | 4232250 |
| 10 | 1969110 |
| 11 | 296676380 |
| 12 | 4798080 |
| 13 | 166289760 |
| 14 | 73765692000 |
| 15 | 712750500 |
| 16 | 50561280 |
| 17 | 33944067893736 |
| 18 | 2139168754800 |
| 19 | 4292572951800 |
| 20 | 1414764341760 |
| 21 | 72461756727360 |
| 22 | 180975331456920 |
| 23 | 1870768457500800 |
| 24 | 5498331930000 |
| 25 | 153698278734000 |