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 | 3 |
| 2 | 8 |
| 3 | 20 |
| 4 | 49 |
| 5 | 119 |
| 6 | 289 |
| 7 | 705 |
| 8 | 1731 |
| 9 | 4283 |
| 10 | 10690 |
| 11 | 26934 |
| 12 | 68531 |
| 13 | 176115 |
| 14 | 457110 |
| 15 | 1198128 |
| 16 | 3170607 |
| 17 | 8468277 |
| 18 | 22818167 |
| 19 | 61999531 |
| 20 | 169778889 |
| 21 | 468292663 |
| 22 | 1300270333 |
| 23 | 3632269293 |
| 24 | 10202425207 |
| 25 | 28798822159 |
| 26 | 81652955889 |
| 27 | 232429744843 |
| 28 | 663969970203 |
| 29 | 1902716831527 |