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) |
|---|---|
| 3 | 0 |
| 4 | 63 |
| 5 | 1566 |
| 6 | 13971 |
| 7 | 77124 |
| 8 | 319206 |
| 9 | 1083723 |
| 10 | 3181401 |
| 11 | 8344854 |
| 12 | 20006349 |
| 13 | 44548227 |
| 14 | 93248628 |
| 15 | 185176866 |
| 16 | 351410664 |
| 17 | 640972980 |
| 18 | 1129067352 |
| 19 | 1928196432 |
| 20 | 3203016813 |