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 | 44 |
| 2 | 198 |
| 3 | 758 |
| 4 | 2824 |
| 5 | 10530 |
| 6 | 39516 |
| 7 | 149274 |
| 8 | 567120 |
| 9 | 2164898 |
| 10 | 8297206 |
| 11 | 31907214 |
| 12 | 123053938 |
| 13 | 475753142 |
| 14 | 1843357752 |
| 15 | 7155936162 |
| 16 | 27826486272 |
| 17 | 108369397602 |
| 18 | 422614721742 |
| 19 | 1650118887102 |
| 20 | 6450143419962 |
| 21 | 25238550057222 |