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 | 0 |
| 3 | 2 |
| 4 | 4 |
| 5 | 12 |
| 6 | 28 |
| 7 | 68 |
| 8 | 156 |
| 9 | 356 |
| 10 | 796 |
| 11 | 1764 |
| 12 | 3868 |
| 13 | 8420 |
| 14 | 18204 |
| 15 | 39140 |
| 16 | 83740 |
| 17 | 178404 |
| 18 | 378652 |
| 19 | 800996 |
| 20 | 1689372 |
| 21 | 3553508 |
| 22 | 7456540 |
| 23 | 15612132 |
| 24 | 32622364 |
| 25 | 68040932 |
| 26 | 141674268 |
| 27 | 294533348 |
| 28 | 611436316 |
| 29 | 1267611876 |
| 30 | 2624702236 |
| 31 | 5428361444 |
| 32 | 11214636828 |