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 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 1 |
| 9 | 36 |
| 10 | 750 |
| 11 | 11880 |
| 12 | 159027 |
| 13 | 1899612 |
| 14 | 20912320 |
| 15 | 216627840 |
| 16 | 2141770488 |
| 17 | 20416870188 |
| 18 | 189100389270 |
| 19 | 1713143123640 |
| 20 | 15314761051669 |
| 21 | 137723007972924 |
| 22 | 1310008783707360 |
| 23 | 14647748873844240 |
| 24 | 215375952901752225 |
| 25 | 4079250159907459680 |