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 | 1 |
| 2 | 2 |
| 3 | 20 |
| 4 | 269 |
| 5 | 8116 |
| 6 | 519400 |
| 7 | 67566361 |
| 8 | 17518353991 |
| 9 | 9334778743018 |
| 10 | 10240638005472594 |
| 11 | 23244895727823155064 |