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 | -1 |
| 3 | 3 |
| 4 | -6 |
| 5 | -1 |
| 6 | 4 |
| 7 | -20 |
| 8 | -20 |
| 9 | 1 |
| 10 | 5 |
| 11 | -50 |
| 12 | -175 |
| 13 | 70 |
| 14 | 1 |
| 15 | 6 |
| 16 | -105 |
| 17 | -980 |
| 18 | 1764 |
| 19 | 252 |
| 20 | -1 |
| 21 | 7 |
| 22 | -196 |
| 23 | -4116 |
| 24 | 24696 |
| 25 | 19404 |
| 26 | -924 |
| 27 | -1 |
| 28 | 8 |
| 29 | -336 |
| 30 | -14112 |
| 31 | 232848 |
| 32 | 731808 |
| 33 | -226512 |
| 34 | -3432 |
| 35 | 1 |
| 36 | 9 |
| 37 | -540 |
| 38 | -41580 |
| 39 | 1646568 |
| 40 | 16818516 |
| 41 | -24293412 |
| 42 | -2760615 |
| 43 | 12870 |
| 44 | 1 |
| 45 | 10 |
| 46 | -825 |
| 47 | -108900 |
| 48 | 9343620 |
| 49 | 267227532 |
| 50 | -1447482465 |