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 | 1 |
| 2 | -369 |
| 3 | -9408 |
| 4 | 22853743 |
| 5 | 4794451200 |
| 6 | -3085237931328 |
| 7 | -819499646151424 |
| 8 | 384739275624398865 |
| 9 | 158606464687370095617 |
| 10 | -50143660099205286196800 |
| 11 | -29592112124024539896414528 |
| 12 | 6061193531453485412550560256 |
| 13 | 5483327637634568394533944708352 |