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) |
|---|---|
| 5 | 1 |
| 6 | -90909 |
| 7 | 9182728191 |
| 8 | -917355454462809 |
| 9 | 91744720010017447191 |
| 10 | -9174380256281734701652809 |
| 11 | 917438943076290926712489347191 |
| 12 | -91743885133148835462057759420652809 |