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) |
|---|---|
| 3 | 1 |
| 4 | 8 |
| 5 | 46 |
| 6 | 234 |
| 7 | 1126 |
| 8 | 5280 |
| 9 | 24508 |
| 10 | 113648 |
| 11 | 529555 |
| 12 | 2488742 |
| 13 | 11824872 |
| 14 | 56879504 |
| 15 | 277155320 |
| 16 | 1368080730 |
| 17 | 6838288158 |
| 18 | 34588110926 |
| 19 | 176875174228 |
| 20 | 913577365466 |
| 21 | 4761373765578 |
| 22 | 25015666670338 |
| 23 | 132372375785294 |
| 24 | 704914546281986 |