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 | 3 |
| 3 | -32 |
| 4 | 465 |
| 5 | -8544 |
| 6 | 190435 |
| 7 | -4996032 |
| 8 | 150869313 |
| 9 | -5155334720 |
| 10 | 196677847971 |
| 11 | -8286870547680 |
| 12 | 382200680031313 |
| 13 | -19152276311294112 |
| 14 | 1036167879649219395 |
| 15 | -60195061159370501504 |
| 16 | 3737352803142621672705 |
| 17 | -246970483156591884266112 |
| 18 | 17306865588065164490357443 |