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 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 40 |
| 5 | 114 |
| 6 | 324 |
| 7 | 920 |
| 8 | 2612 |
| 9 | 7416 |
| 10 | 21056 |
| 11 | 59784 |
| 12 | 169744 |
| 13 | 481952 |
| 14 | 1368400 |
| 15 | 3885280 |
| 16 | 11031424 |
| 17 | 31321376 |
| 18 | 88930368 |
| 19 | 252498816 |
| 20 | 716916544 |
| 21 | 2035531648 |
| 22 | 5779458048 |
| 23 | 16409538688 |
| 24 | 46591385856 |
| 25 | 132286304768 |
| 26 | 375598753024 |
| 27 | 1066432564736 |
| 28 | 3027907856384 |