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 | 0 |
| 1 | 32 |
| 2 | 7776 |
| 3 | 248832 |
| 4 | 3200000 |
| 5 | 24300000 |
| 6 | 130691232 |
| 7 | 550731776 |
| 8 | 1934917632 |
| 9 | 5904900000 |
| 10 | 16105100000 |
| 11 | 40074642432 |
| 12 | 92389579776 |
| 13 | 199690286432 |
| 14 | 408410100000 |
| 15 | 796262400000 |
| 16 | 1488827973632 |
| 17 | 2682916351776 |
| 18 | 4678757435232 |
| 19 | 7923516800000 |
| 20 | 13069123200000 |