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 | -3 |
| 2 | 6 |
| 3 | -10 |
| 4 | 12 |
| 5 | -9 |
| 6 | -2 |
| 7 | 24 |
| 8 | -54 |
| 9 | 80 |
| 10 | -84 |
| 11 | 42 |
| 12 | 66 |
| 13 | -234 |
| 14 | 420 |
| 15 | -536 |
| 16 | 450 |
| 17 | -39 |
| 18 | -740 |
| 19 | 1770 |
| 20 | -2688 |
| 21 | 2898 |
| 22 | -1722 |
| 23 | -1320 |
| 24 | 6078 |
| 25 | -11349 |
| 26 | 14736 |
| 27 | -12992 |
| 28 | 3084 |
| 29 | 15999 |
| 30 | -41212 |
| 31 | 64032 |
| 32 | -70788 |
| 33 | 46020 |
| 34 | 20778 |
| 35 | -126132 |
| 36 | 244120 |
| 37 | -323421 |
| 38 | 295410 |
| 39 | -96848 |
| 40 | -293868 |
| 41 | 815829 |
| 42 | -1297972 |