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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 3 |
| 6 | 9 |
| 7 | 63 |
| 8 | 63 |
| 9 | 567 |
| 10 | 567 |
| 11 | 6237 |
| 12 | 18711 |
| 13 | 18711 |
| 14 | 130977 |
| 15 | 392931 |
| 16 | 392931 |
| 17 | 392931 |
| 18 | 3536379 |
| 19 | 67191201 |
| 20 | 67191201 |
| 21 | 1411015221 |
| 22 | 15521167431 |
| 23 | 356986850913 |
| 24 | 1070960552739 |
| 25 | 1070960552739 |
| 26 | 1070960552739 |
| 27 | 28915934923953 |