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 | 6 |
| 3 | -3 |
| 4 | -16 |
| 5 | 8 |
| 6 | -48 |
| 7 | 4 |
| 8 | 30 |
| 9 | -20 |
| 10 | 140 |
| 11 | 10 |
| 12 | -140 |
| 13 | 420 |
| 14 | -5 |
| 15 | -48 |
| 16 | 36 |
| 17 | -288 |
| 18 | -24 |
| 19 | 384 |
| 20 | -1280 |
| 21 | 12 |
| 22 | -192 |
| 23 | -96 |
| 24 | 1920 |
| 25 | -3840 |
| 26 | 6 |
| 27 | 70 |
| 28 | -56 |
| 29 | 504 |
| 30 | 42 |
| 31 | -756 |
| 32 | 2772 |
| 33 | -28 |
| 34 | 504 |
| 35 | 252 |
| 36 | -5544 |
| 37 | 12012 |
| 38 | 14 |
| 39 | -252 |
| 40 | -252 |
| 41 | 2772 |
| 42 | 2772 |
| 43 | -24024 |
| 44 | 36036 |
| 45 | -7 |
| 46 | -96 |
| 47 | 80 |
| 48 | -800 |
| 49 | -64 |
| 50 | 1280 |
| 51 | -5120 |
| 52 | 48 |
| 53 | -960 |
| 54 | -480 |
| 55 | 11520 |
| 56 | -26880 |
| 57 | -32 |
| 58 | 640 |
| 59 | 640 |
| 60 | -7680 |