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 | 30 |
| 2 | 88 |
| 3 | 204 |
| 4 | 548 |
| 5 | 1460 |
| 6 | 4006 |
| 7 | 11090 |
| 8 | 31036 |
| 9 | 87468 |
| 10 | 248018 |
| 11 | 706670 |
| 12 | 2021738 |
| 13 | 5804010 |
| 14 | 16711552 |
| 15 | 48241364 |
| 16 | 139572076 |
| 17 | 404612780 |
| 18 | 1175026834 |
| 19 | 3417771710 |
| 20 | 9955368238 |
| 21 | 29035695998 |
| 22 | 84784671532 |
| 23 | 247838482400 |
| 24 | 725183659570 |