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 | -30 |
| 3 | 415 |
| 4 | -3500 |
| 5 | 20023 |
| 6 | -81622 |
| 7 | 241605 |
| 8 | -517360 |
| 9 | 780286 |
| 10 | -782108 |
| 11 | 463310 |
| 12 | -121020 |
| 13 | 0 |