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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 12 |
| 7 | 12 |
| 8 | 96 |
| 9 | 288 |
| 10 | 2880 |
| 11 | 2880 |
| 12 | 414720 |
| 13 | 414720 |
| 14 | 5806080 |
| 15 | 87091200 |
| 16 | 5573836800 |
| 17 | 5573836800 |
| 18 | 1805923123200 |
| 19 | 1805923123200 |
| 20 | 722369249280000 |
| 21 | 15169754234880000 |
| 22 | 333734593167360000 |
| 23 | 333734593167360000 |
| 24 | 4613547015945584640000 |
| 25 | 23067735079727923200000 |