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 | 1 |
| 4 | 0 |
| 5 | 12 |
| 6 | 4 |
| 7 | 129 |
| 8 | 72 |
| 9 | 1332 |
| 10 | 960 |
| 11 | 13419 |
| 12 | 11372 |
| 13 | 132900 |
| 14 | 126396 |
| 15 | 1299851 |
| 16 | 1349784 |
| 17 | 12592440 |
| 18 | 14023944 |
| 19 | 121074183 |
| 20 | 142818336 |
| 21 | 1157026804 |
| 22 | 1432470300 |
| 23 | 11001347199 |
| 24 | 14196860272 |
| 25 | 104161648860 |
| 26 | 139351826712 |
| 27 | 982653092725 |
| 28 | 1357030991292 |
| 29 | 9241395939636 |