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 | 1 |
| 1 | 3 |
| 2 | 90 |
| 3 | 21897 |
| 4 | 46281375 |
| 5 | 882516062106 |
| 6 | 153201395082609531 |
| 7 | 241604140428719375972139 |
| 8 | 3448358784659838019970862469260 |
| 9 | 444238039567848645977924129826080612043 |