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 | 0 |
| 3 | -1 |
| 4 | -1 |
| 5 | 3 |
| 6 | 7 |
| 7 | -8 |
| 8 | -45 |
| 9 | 0 |
| 10 | 264 |
| 11 | 273 |
| 12 | -1365 |
| 13 | -3192 |
| 14 | 5508 |
| 15 | 27132 |
| 16 | -7752 |
| 17 | -193743 |
| 18 | -158631 |
| 19 | 1177209 |
| 20 | 2417415 |
| 21 | -5673525 |
| 22 | -23595585 |
| 23 | 14488110 |
| 24 | 187050435 |
| 25 | 104481780 |
| 26 | -1251127512 |
| 27 | -2178989008 |
| 28 | 6775504088 |
| 29 | 23824892148 |
| 30 | -23395134188 |
| 31 | -204487059656 |
| 32 | -57418615353 |
| 33 | 1471227866951 |