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 | 9 |
| 3 | 144 |
| 4 | 3312 |
| 5 | 99360 |
| 6 | 3676320 |
| 7 | 161758080 |
| 8 | 8249662080 |
| 9 | 478480400640 |
| 10 | 31101226041600 |
| 11 | 2239288274995200 |
| 12 | 176903773724620800 |
| 13 | 15213724540317388800 |
| 14 | 1414876382249517158400 |
| 15 | 141487638224951715840000 |
| 16 | 15139177290069833594880000 |
| 17 | 1725866211067961029816320000 |