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 | -31 |
| 3 | -95 |
| 4 | 2881 |
| 5 | 15041 |
| 6 | -445919 |
| 7 | -3333791 |
| 8 | 96552065 |
| 9 | 950002561 |
| 10 | -26856992159 |
| 11 | -330857811679 |
| 12 | 9122803428289 |
| 13 | 136172203113025 |
| 14 | -3658914023055199 |
| 15 | -64664061017690399 |
| 16 | 1691614670048805121 |
| 17 | 34799613911106289409 |
| 18 | -885438766595443696415 |