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 | -2 |
| 2 | 1 |
| 3 | 8 |
| 4 | -6 |
| 5 | 1 |
| 6 | -40 |
| 7 | 36 |
| 8 | -10 |
| 9 | 1 |
| 10 | 224 |
| 11 | -224 |
| 12 | 80 |
| 13 | -14 |
| 14 | 1 |
| 15 | -1344 |
| 16 | 1440 |
| 17 | -600 |
| 18 | 140 |
| 19 | -18 |
| 20 | 1 |
| 21 | 8448 |
| 22 | -9504 |
| 23 | 4400 |
| 24 | -1232 |
| 25 | 216 |
| 26 | -22 |
| 27 | 1 |
| 28 | -54912 |
| 29 | 64064 |
| 30 | -32032 |
| 31 | 10192 |
| 32 | -2184 |
| 33 | 308 |
| 34 | -26 |
| 35 | 1 |
| 36 | 366080 |
| 37 | -439296 |
| 38 | 232960 |
| 39 | -81536 |
| 40 | 20160 |
| 41 | -3520 |
| 42 | 416 |
| 43 | -30 |
| 44 | 1 |
| 45 | -2489344 |
| 46 | 3055104 |
| 47 | -1697280 |
| 48 | 639744 |
| 49 | -176256 |
| 50 | 35904 |
| 51 | -5304 |
| 52 | 540 |
| 53 | -34 |
| 54 | 1 |