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 | 3 |
| 3 | 6 |
| 4 | 14 |
| 5 | 30 |
| 6 | 69 |
| 7 | 153 |
| 8 | 345 |
| 9 | 771 |
| 10 | 1730 |
| 11 | 3873 |
| 12 | 8682 |
| 13 | 19450 |
| 14 | 43590 |
| 15 | 97668 |
| 16 | 218864 |
| 17 | 490416 |
| 18 | 1098933 |
| 19 | 2462458 |
| 20 | 5517870 |
| 21 | 12364356 |
| 22 | 27705944 |
| 23 | 62083134 |
| 24 | 139115247 |
| 25 | 311727845 |
| 26 | 698516370 |
| 27 | 1565227653 |
| 28 | 3507344882 |
| 29 | 7859219406 |
| 30 | 17610851898 |