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 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | -2 |
| 5 | 3 |
| 6 | 0 |
| 7 | 3 |
| 8 | -18 |
| 9 | 16 |
| 10 | 0 |
| 11 | -4 |
| 12 | 72 |
| 13 | -192 |
| 14 | 125 |
| 15 | 0 |
| 16 | 5 |
| 17 | -240 |
| 18 | 1440 |
| 19 | -2500 |
| 20 | 1296 |
| 21 | 0 |
| 22 | -6 |
| 23 | 720 |
| 24 | -8640 |
| 25 | 30000 |
| 26 | -38880 |
| 27 | 16807 |
| 28 | 0 |
| 29 | 7 |
| 30 | -2016 |
| 31 | 45360 |
| 32 | -280000 |
| 33 | 680400 |
| 34 | -705894 |
| 35 | 262144 |
| 36 | 0 |
| 37 | -8 |
| 38 | 5376 |
| 39 | -217728 |
| 40 | 2240000 |
| 41 | -9072000 |
| 42 | 16941456 |
| 43 | -14680064 |
| 44 | 4782969 |