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 | 12 |
| 4 | 55 |
| 5 | 273 |
| 6 | 1372 |
| 7 | 6824 |
| 8 | 33489 |
| 9 | 162405 |
| 10 | 779801 |
| 11 | 3713436 |
| 12 | 17560803 |
| 13 | 82553597 |
| 14 | 386105790 |
| 15 | 1797803248 |
| 16 | 8338313697 |
| 17 | 38539754649 |
| 18 | 177581276639 |
| 19 | 815982230060 |
| 20 | 3740047627071 |
| 21 | 17103604731961 |
| 22 | 78054858200448 |
| 23 | 355541644914072 |
| 24 | 1616688603539025 |