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 | 3 |
| 1 | 60 |
| 2 | 630 |
| 3 | 5040 |
| 4 | 34650 |
| 5 | 216216 |
| 6 | 1261260 |
| 7 | 7001280 |
| 8 | 37413090 |
| 9 | 193993800 |
| 10 | 981608628 |
| 11 | 4867480800 |
| 12 | 23728968900 |
| 13 | 114011377200 |
| 14 | 540972351000 |
| 15 | 2538963567360 |
| 16 | 11802213457650 |
| 17 | 54396360988200 |
| 18 | 248812984520100 |
| 19 | 1130341536324000 |
| 20 | 5103492036502860 |
| 21 | 22913637714910800 |