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 | -3 |
| 2 | 8 |
| 3 | -17 |
| 4 | 20 |
| 5 | 23 |
| 6 | -50 |
| 7 | -1185 |
| 8 | 6648 |
| 9 | 20143 |
| 10 | -372646 |
| 11 | 179111 |
| 12 | 25378468 |
| 13 | -126050121 |
| 14 | -1849977930 |
| 15 | 23353880527 |
| 16 | 109161798512 |
| 17 | -3986970251809 |
| 18 | 6487865966386 |
| 19 | 680166849412311 |
| 20 | -5885809282265124 |
| 21 | -109572316727641433 |
| 22 | 2250978116175344846 |
| 23 | 11909910338327490623 |