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 | 0 |
| 1 | 2 |
| 2 | -44 |
| 3 | 2166 |
| 4 | -196888 |
| 5 | 28730410 |
| 6 | -6148123332 |
| 7 | 1813990148894 |
| 8 | -705775346640176 |
| 9 | 350112935442888018 |
| 10 | -215681051222514096220 |
| 11 | 161537815119247080938182 |
| 12 | -144555133640020128085896264 |
| 13 | 152323571317104251881943249786 |