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 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 3 |
| 6 | 3 |
| 7 | 21 |
| 8 | 21 |
| 9 | 189 |
| 10 | 189 |
| 11 | 2079 |
| 12 | 2079 |
| 13 | 27027 |
| 14 | 27027 |
| 15 | 27027 |
| 16 | 27027 |
| 17 | 459459 |
| 18 | 459459 |
| 19 | 8729721 |
| 20 | 8729721 |
| 21 | 183324141 |
| 22 | 183324141 |
| 23 | 4216455243 |
| 24 | 4216455243 |
| 25 | 4216455243 |
| 26 | 4216455243 |
| 27 | 113844291561 |
| 28 | 113844291561 |
| 29 | 3301484455269 |
| 30 | 3301484455269 |
| 31 | 102346018113339 |
| 32 | 102346018113339 |
| 33 | 3377418597740187 |