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 | -49 |
| 4 | -719 |
| 5 | -14077 |
| 6 | -344909 |
| 7 | -10152829 |
| 8 | -349045535 |
| 9 | -13727327833 |
| 10 | -607873987637 |
| 11 | -29931556660105 |
| 12 | -1622308999459631 |
| 13 | -95982568510668373 |
| 14 | -6155361624644676989 |
| 15 | -425321834949751148053 |
| 16 | -31502433469012320013631 |
| 17 | -2489898822489054343250737 |
| 18 | -209178052238110675644666341 |