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) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | 1 |
| 4 | 7 |
| 5 | -4 |
| 6 | 1 |
| 7 | -36 |
| 8 | 21 |
| 9 | -6 |
| 10 | 1 |
| 11 | 246 |
| 12 | -144 |
| 13 | 42 |
| 14 | -8 |
| 15 | 1 |
| 16 | -2100 |
| 17 | 1230 |
| 18 | -360 |
| 19 | 70 |
| 20 | -10 |
| 21 | 1 |
| 22 | 21510 |
| 23 | -12600 |
| 24 | 3690 |
| 25 | -720 |
| 26 | 105 |
| 27 | -12 |
| 28 | 1 |
| 29 | -257040 |
| 30 | 150570 |
| 31 | -44100 |
| 32 | 8610 |
| 33 | -1260 |
| 34 | 147 |
| 35 | -14 |
| 36 | 1 |
| 37 | 3510360 |
| 38 | -2056320 |
| 39 | 602280 |
| 40 | -117600 |
| 41 | 17220 |
| 42 | -2016 |
| 43 | 196 |
| 44 | -16 |
| 45 | 1 |
| 46 | -53933040 |