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 | 0 |
| 1 | 6 |
| 2 | 48 |
| 3 | 97 |
| 4 | 440 |
| 5 | 14846 |
| 6 | 31653 |
| 7 | 31653 |
| 8 | 1678739 |
| 9 | 1678739 |
| 10 | 122739560 |
| 11 | 1535115805 |
| 12 | 3512442548 |
| 13 | 58877591352 |
| 14 | 155766601759 |
| 15 | 2190435820306 |
| 16 | 30675804879964 |
| 17 | 97141666019166 |
| 18 | 97141666019166 |
| 19 | 3353968861840064 |
| 20 | 48949549603332636 |
| 21 | 288326348496168639 |