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) |
|---|---|
| 6 | 1 |
| 7 | 11 |
| 8 | 84 |
| 9 | 520 |
| 10 | 2835 |
| 11 | 14133 |
| 12 | 65960 |
| 13 | 292536 |
| 14 | 1245789 |
| 15 | 5132375 |
| 16 | 20569512 |
| 17 | 80541300 |
| 18 | 309143065 |
| 19 | 1166302239 |
| 20 | 4334300976 |
| 21 | 15895046840 |
| 22 | 57608669274 |
| 23 | 206606077758 |
| 24 | 733992204988 |
| 25 | 2585415612500 |
| 26 | 9036556157100 |
| 27 | 31362262768684 |
| 28 | 108144498780096 |
| 29 | 370700681812032 |