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 | 0 |
| 2 | 1 |
| 3 | 80 |
| 4 | 1224 |
| 5 | 9152 |
| 6 | 45276 |
| 7 | 170784 |
| 8 | 534464 |
| 9 | 1438848 |
| 10 | 3507102 |
| 11 | 7711600 |
| 12 | 16053728 |
| 13 | 30831552 |
| 14 | 57578072 |
| 15 | 100382304 |
| 16 | 173117952 |
| 17 | 280579200 |
| 18 | 455656725 |
| 19 | 697508496 |
| 20 | 1079398256 |
| 21 | 1580599552 |
| 22 | 2351610612 |
| 23 | 3315523424 |
| 24 | 4785293568 |
| 25 | 6534524160 |
| 26 | 9173253878 |
| 27 | 12226860576 |