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 | 0 |
| 4 | 2 |
| 5 | 0 |
| 6 | -5 |
| 7 | -7 |
| 8 | 14 |
| 9 | 42 |
| 10 | -12 |
| 11 | -198 |
| 12 | -165 |
| 13 | 715 |
| 14 | 1573 |
| 15 | -1573 |
| 16 | -9282 |
| 17 | -3094 |
| 18 | 41548 |
| 19 | 63308 |
| 20 | -131784 |
| 21 | -468996 |
| 22 | 111758 |
| 23 | 2496144 |
| 24 | 2369851 |
| 25 | -9926455 |
| 26 | -23864570 |
| 27 | 22785180 |
| 28 | 150243015 |
| 29 | 60480225 |
| 30 | -709314480 |
| 31 | -1161220320 |
| 32 | 2325542190 |
| 33 | 8874775170 |
| 34 | -1613776920 |