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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 39 |
| 6 | 161 |
| 7 | 698 |
| 8 | 3126 |
| 9 | 14360 |
| 10 | 67276 |
| 11 | 320229 |
| 12 | 1544257 |
| 13 | 7528577 |
| 14 | 37044530 |
| 15 | 183733552 |
| 16 | 917598103 |
| 17 | 4610484729 |
| 18 | 23289784660 |
| 19 | 118209987295 |
| 20 | 602556082765 |
| 21 | 3083273829240 |
| 22 | 15832177371585 |
| 23 | 81554320766310 |
| 24 | 421320423560400 |
| 25 | 2182395044437686 |
| 26 | 11332298321692704 |