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 | 1 |
| 2 | -3 |
| 3 | 37 |
| 4 | -1007 |
| 5 | 47901 |
| 6 | -3514499 |
| 7 | 367671697 |
| 8 | -51952729023 |
| 9 | 9529552851193 |
| 10 | -2201241933756899 |
| 11 | 625136460673954461 |
| 12 | -214066473170125310063 |
| 13 | 86976878219664125966677 |
| 14 | -41368038169392401671082787 |
| 15 | 22767783580493235411255966601 |
| 16 | -14356419990032448099044028030719 |