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 | 0 |
| 3 | -3 |
| 4 | -2 |
| 5 | -7 |
| 6 | -4 |
| 7 | -23 |
| 8 | -6 |
| 9 | -45 |
| 10 | -8 |
| 11 | 655 |
| 12 | -10 |
| 13 | -5483 |
| 14 | -12 |
| 15 | 929361 |
| 16 | -14 |
| 17 | -3202321 |
| 18 | -16 |
| 19 | 221930513 |
| 20 | -18 |
| 21 | -4722116559 |
| 22 | -20 |
| 23 | 968383680659 |
| 24 | -22 |
| 25 | -14717667114197 |
| 26 | -24 |
| 27 | 2093660879252571 |
| 28 | -26 |
| 29 | -86125672563201235 |
| 30 | -28 |
| 31 | 129848163681107301025 |
| 32 | -30 |