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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 16 |
| 6 | 47 |
| 7 | 132 |
| 8 | 410 |
| 9 | 1254 |
| 10 | 4052 |
| 11 | 12818 |
| 12 | 42783 |
| 13 | 139082 |
| 14 | 469924 |
| 15 | 1563606 |
| 16 | 5353966 |
| 17 | 18065348 |
| 18 | 62491018 |
| 19 | 213391790 |
| 20 | 743836996 |
| 21 | 2565135934 |
| 22 | 8994087070 |
| 23 | 31251762932 |
| 24 | 110245063771 |
| 25 | 385443583008 |
| 26 | 1365151504722 |
| 27 | 4800376128986 |
| 28 | 17070221456536 |
| 29 | 60289267885410 |