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 | 560 |
| 3 | 19600 |
| 4 | 43680 |
| 5 | 45760 |
| 6 | 893200 |
| 7 | 1521520 |
| 8 | 7207200 |
| 9 | 29269240 |
| 10 | 2845642800 |
| 11 | 22778408800 |
| 12 | 26595476600 |
| 13 | 59777945920 |
| 14 | 199910480000 |
| 15 | 239526427140 |
| 16 | 249466897680 |
| 17 | 283345302240 |
| 18 | 3280499995500 |
| 19 | 20894643369600 |
| 20 | 115333903584900 |
| 21 | 408688050971200 |
| 22 | 706949015272500 |
| 23 | 4613394351142500 |