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) |
|---|---|
| 1 | 1 |
| 2 | 20 |
| 3 | 295 |
| 4 | 3485 |
| 5 | 33496 |
| 6 | 247799 |
| 7 | 1010905 |
| 8 | -7422100 |
| 9 | -238118825 |
| 10 | -3513857515 |
| 11 | -38530770320 |
| 12 | -329008652665 |
| 13 | -1926925302575 |
| 14 | -594574697500 |
| 15 | 188633380315975 |
| 16 | 3451130126965325 |
| 17 | 42502627523897800 |
| 18 | 406764806549554775 |
| 19 | 2912899847916711625 |