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 | 1 |
| 2 | -5 |
| 3 | -35 |
| 4 | -29 |
| 5 | 751 |
| 6 | 3991 |
| 7 | -4115 |
| 8 | -137885 |
| 9 | -495269 |
| 10 | 2114245 |
| 11 | 25786795 |
| 12 | 50109775 |
| 13 | -627370925 |
| 14 | -4643568305 |
| 15 | -495798035 |
| 16 | 157753390435 |
| 17 | 768269873875 |
| 18 | -1851203127335 |
| 19 | -35924154988865 |
| 20 | -107001450483779 |
| 21 | 763444753890721 |
| 22 | 7510024190977105 |
| 23 | 8899910747771995 |