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 | 15 |
| 2 | 960 |
| 3 | 61440 |
| 4 | 3932160 |
| 5 | 251658240 |
| 6 | 16106127360 |
| 7 | 1030792151040 |
| 8 | 65970697666560 |
| 9 | 4222124650659840 |
| 10 | 270215977642229760 |
| 11 | 17293822569102704640 |
| 12 | 1106804644422573096960 |
| 13 | 70835497243044678205440 |
| 14 | 4533471823554859405148160 |
| 15 | 290142196707511001929482240 |
| 16 | 18569100589280704123486863360 |