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 | 5 |
| 2 | 20 |
| 3 | 65 |
| 4 | 185 |
| 5 | 481 |
| 6 | 1165 |
| 7 | 2665 |
| 8 | 5822 |
| 9 | 12230 |
| 10 | 24842 |
| 11 | 49010 |
| 12 | 94235 |
| 13 | 177087 |
| 14 | 326015 |
| 15 | 589128 |
| 16 | 1046705 |
| 17 | 1831065 |
| 18 | 3157789 |
| 19 | 5374390 |
| 20 | 9035539 |
| 21 | 15018300 |
| 22 | 24697480 |
| 23 | 40210481 |
| 24 | 64854575 |
| 25 | 103679156 |
| 26 | 164363280 |
| 27 | 258508230 |
| 28 | 403531208 |
| 29 | 625425005 |