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 | 2 |
| 1 | 4 |
| 2 | 6 |
| 3 | 14 |
| 4 | 86 |
| 5 | 3614 |
| 6 | 6526886 |
| 7 | 21300113901614 |
| 8 | 226847426110843688722000886 |
| 9 | 25729877366557343481074291996721923093306518970391614 |