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 | 12 |
| 3 | 120 |
| 4 | 1260 |
| 5 | 10080 |
| 6 | 110880 |
| 7 | 1081080 |
| 8 | 10810800 |
| 9 | 110270160 |
| 10 | 1102701600 |
| 11 | 10475665200 |
| 12 | 128501493120 |
| 13 | 1124388064800 |
| 14 | 13492656777600 |
| 15 | 130429015516800 |
| 16 | 1010824870255200 |
| 17 | 10108248702552000 |
| 18 | 106858629141264000 |