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 | 12 |
| 4 | 620 |
| 5 | 87304 |
| 6 | 26312976 |
| 7 | 14616808192 |
| 8 | 13525751027392 |
| 9 | 19385778269260800 |
| 10 | 40739017561997799680 |
| 11 | 120278021410937387514880 |
| 12 | 482113680618029292368686080 |
| 13 | 2551154673732472157928033617920 |
| 14 | 17410560213476464590484763013222400 |