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) |
|---|---|
| 1 | 0 |
| 2 | 3 |
| 3 | 1 |
| 4 | 4 |
| 5 | 4 |
| 6 | 11 |
| 7 | 26 |
| 8 | 66 |
| 9 | 171 |
| 10 | 462 |
| 11 | 1248 |
| 12 | 3419 |
| 13 | 9450 |
| 14 | 26334 |
| 15 | 73697 |
| 16 | 206960 |
| 17 | 582316 |
| 18 | 1640549 |
| 19 | 4625476 |
| 20 | 13047636 |
| 21 | 36816651 |
| 22 | 103906694 |
| 23 | 293290860 |
| 24 | 827923703 |
| 25 | 2337253142 |
| 26 | 6598367806 |
| 27 | 18628473233 |
| 28 | 52592572696 |
| 29 | 148482655256 |
| 30 | 419208157101 |