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 | 2 |
| 3 | 2 |
| 4 | -7 |
| 5 | 6 |
| 6 | -6 |
| 7 | 29 |
| 8 | -46 |
| 9 | 24 |
| 10 | 24 |
| 11 | -146 |
| 12 | 329 |
| 13 | -326 |
| 14 | 120 |
| 15 | -120 |
| 16 | 874 |
| 17 | -2521 |
| 18 | 3604 |
| 19 | -2556 |
| 20 | 720 |
| 21 | 720 |
| 22 | -6084 |
| 23 | 21244 |
| 24 | -39271 |
| 25 | 40564 |
| 26 | -22212 |
| 27 | 5040 |
| 28 | -5040 |
| 29 | 48348 |
| 30 | -197380 |
| 31 | 444849 |
| 32 | -598116 |
| 33 | 479996 |
| 34 | -212976 |
| 35 | 40320 |
| 36 | 40320 |
| 37 | -432144 |
| 38 | 2014172 |
| 39 | -5335212 |
| 40 | 8788569 |
| 41 | -9223012 |
| 42 | 6023772 |
| 43 | -2239344 |
| 44 | 362880 |