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 | -1 |
| 3 | 2 |
| 4 | -4 |
| 5 | 1 |
| 6 | 6 |
| 7 | -16 |
| 8 | 8 |
| 9 | -1 |
| 10 | 36 |
| 11 | -108 |
| 12 | 69 |
| 13 | -15 |
| 14 | 1 |
| 15 | 360 |
| 16 | -1152 |
| 17 | 834 |
| 18 | -230 |
| 19 | 26 |
| 20 | -1 |
| 21 | 5280 |
| 22 | -17696 |
| 23 | 14368 |
| 24 | -4668 |
| 25 | 682 |
| 26 | -44 |
| 27 | 1 |
| 28 | 147840 |
| 29 | -506048 |
| 30 | 426568 |
| 31 | -147856 |
| 32 | 24262 |
| 33 | -1952 |
| 34 | 73 |
| 35 | -1 |
| 36 | 6800640 |
| 37 | -23573888 |
| 38 | 20317360 |