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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 120 |
| 4 | 2640 |
| 5 | 76560 |
| 6 | 2756160 |
| 7 | 118514880 |
| 8 | 5925744000 |
| 9 | 337767408000 |
| 10 | 21617114112000 |
| 11 | 1534815101952000 |
| 12 | 119715577952256000 |
| 13 | 10175824125941760000 |
| 14 | 936175819586641920000 |
| 15 | 92681406139077550080000 |
| 16 | 9824229050742220308480000 |
| 17 | 1110137882733870894858240000 |