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 | -4 |
| 1 | 4 |
| 2 | 8 |
| 3 | 2 |
| 4 | -10 |
| 5 | 0 |
| 6 | 12 |
| 7 | 0 |
| 8 | 16 |
| 9 | -32 |
| 10 | -16 |
| 11 | 32 |
| 12 | -4 |
| 13 | -4 |
| 14 | 120 |
| 15 | -120 |
| 16 | -120 |
| 17 | 120 |
| 18 | 0 |
| 19 | -96 |
| 20 | -96 |
| 21 | 960 |
| 22 | -480 |
| 23 | -864 |
| 24 | 576 |
| 25 | 80 |
| 26 | 80 |
| 27 | -1680 |
| 28 | -1680 |
| 29 | 8400 |
| 30 | -1680 |
| 31 | -6720 |
| 32 | 3360 |
| 33 | 0 |
| 34 | 3840 |
| 35 | 3840 |
| 36 | -26880 |
| 37 | -26880 |
| 38 | 80640 |
| 39 | 0 |
| 40 | -57600 |
| 41 | 23040 |
| 42 | -6048 |
| 43 | -6048 |
| 44 | 120960 |
| 45 | 120960 |
| 46 | -423360 |
| 47 | -423360 |
| 48 | 846720 |
| 49 | 120960 |
| 50 | -544320 |
| 51 | 181440 |