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 | 6 |
| 2 | 36 |
| 3 | 630 |
| 4 | 3570 |
| 5 | 61776 |
| 6 | 349866 |
| 7 | 6053460 |
| 8 | 34283340 |
| 9 | 593177346 |
| 10 | 3359417496 |
| 11 | 58125326490 |
| 12 | 329188631310 |
| 13 | 5695688818716 |
| 14 | 32257126450926 |
| 15 | 558119378907720 |
| 16 | 3160869203559480 |
| 17 | 54690003444137886 |
| 18 | 309732924822378156 |
| 19 | 5359062218146605150 |
| 20 | 30350665763389499850 |