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 | -7 |
| 3 | -1 |
| 4 | 3121 |
| 5 | 132959 |
| 6 | -1261591 |
| 7 | -889217057 |
| 8 | -79029091743 |
| 9 | 5889540654911 |
| 10 | 3289057601679065 |
| 11 | 395957721046153023 |
| 12 | -120519140613246313327 |
| 13 | -71865162873642033099361 |
| 14 | -9267049529998625177827639 |
| 15 | 8376363338336819515365004319 |
| 16 | 5693280488360087435524724806849 |