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) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 38 |
| 4 | 684 |
| 5 | 50224 |
| 6 | 13946352 |
| 7 | 14061131152 |
| 8 | 50947324188128 |
| 9 | 666754350781269760 |
| 10 | 31763991166456912086656 |
| 11 | 5550343429517595744902558208 |
| 12 | 3581353054755185129132443153728000 |