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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 26 |
| 7 | 702 |
| 8 | 11734 |
| 9 | 156976 |
| 10 | 1847636 |
| 11 | 20046784 |
| 12 | 205891684 |
| 13 | 2034977036 |
| 14 | 19567350334 |
| 15 | 184421027812 |
| 16 | 1712803733352 |
| 17 | 15736451922346 |
| 18 | 143435108141199 |
| 19 | 1299841823088167 |
| 20 | 11730670902611152 |
| 21 | 105559108929460026 |