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 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 1 |
| 7 | 0 |
| 8 | 1 |
| 9 | 0 |
| 10 | 25 |
| 11 | 0 |
| 12 | 477481 |
| 13 | 0 |
| 14 | 49 |
| 15 | 0 |
| 16 | 13082689 |
| 17 | 0 |
| 18 | 1924313689 |
| 19 | 0 |
| 20 | 30489001321 |
| 21 | 0 |
| 22 | 730192467169 |
| 23 | 0 |
| 24 | 55867983514256281 |
| 25 | 0 |
| 26 | 73155570928609 |
| 27 | 0 |
| 28 | 564036899167989738841 |
| 29 | 0 |
| 30 | 74232720893311466588760025 |
| 31 | 0 |
| 32 | 59433630916551169012841089 |
| 33 | 0 |
| 34 | 6644474695172651051906689 |