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 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 40 |
| 6 | 166 |
| 7 | 749 |
| 8 | 3683 |
| 9 | 19275 |
| 10 | 107806 |
| 11 | 640970 |
| 12 | 4024912 |
| 13 | 26653653 |
| 14 | 185401581 |
| 15 | 1350624721 |
| 16 | 10282222002 |
| 17 | 81592209580 |
| 18 | 673535269054 |
| 19 | 5773214891137 |
| 20 | 51291776763863 |
| 21 | 471617190143567 |
| 22 | 4481375500319334 |
| 23 | 43947651280912186 |
| 24 | 444258975094335440 |