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 | 24 |
| 2 | -486 |
| 3 | 18960 |
| 4 | -866028 |
| 5 | 43409520 |
| 6 | -2305522278 |
| 7 | 127386486480 |
| 8 | -7243559214894 |
| 9 | 420974335099176 |
| 10 | -24888628571711040 |
| 11 | 1491922400816664432 |
| 12 | -90454843306100805420 |
| 13 | 5536766153219810009520 |
| 14 | -341663245004722577661324 |
| 15 | 21230836457057377337055600 |
| 16 | -1327296238831338778081286796 |