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 | 0 |
| 1 | 0 |
| 2 | 5 |
| 3 | 17 |
| 4 | 50 |
| 5 | 136 |
| 6 | 352 |
| 7 | 880 |
| 8 | 2144 |
| 9 | 5120 |
| 10 | 12032 |
| 11 | 27904 |
| 12 | 64000 |
| 13 | 145408 |
| 14 | 327680 |
| 15 | 733184 |
| 16 | 1630208 |
| 17 | 3604480 |
| 18 | 7929856 |
| 19 | 17367040 |
| 20 | 37879808 |
| 21 | 82313216 |
| 22 | 178257920 |
| 23 | 384827392 |
| 24 | 828375040 |
| 25 | 1778384896 |
| 26 | 3808428032 |
| 27 | 8136949760 |
| 28 | 17347641344 |