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 | 649 |
| 4 | 51841 |
| 5 | 6825601 |
| 6 | 1489881601 |
| 7 | 511943846401 |
| 8 | 262183528857601 |
| 9 | 191138113268121601 |
| 10 | 191138824350351360001 |
| 11 | 254405870811372994560001 |
| 12 | 439613359905259699568640001 |
| 13 | 965830554503712299093852160001 |