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 | 4 |
| 4 | 56 |
| 5 | 2640 |
| 6 | 411840 |
| 7 | 210613312 |
| 8 | 351102230528 |
| 9 | 1901049105201408 |
| 10 | 33349238079515381760 |
| 11 | 1892086487183556298556416 |
| 12 | 346728396311328694807284940800 |
| 13 | 205021218459835103075295973360128000 |
| 14 | 390870571052378289975757743555515137130496 |