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 | 9 |
| 3 | -177 |
| 4 | 6097 |
| 5 | -325249 |
| 6 | 24807321 |
| 7 | -2558036145 |
| 8 | 342232522657 |
| 9 | -57569080467073 |
| 10 | 11879658510739497 |
| 11 | -2948163649552594737 |
| 12 | 865683568087537789297 |
| 13 | -296699416391356495667713 |
| 14 | 117330699580950022391960505 |