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 | -6 |
| 4 | 29 |
| 5 | 31 |
| 6 | -283 |
| 7 | 245 |
| 8 | 298 |
| 9 | -286 |
| 10 | -108 |
| 11 | 119 |
| 12 | -3106 |
| 13 | 29469 |
| 14 | -104585 |
| 15 | -220481 |
| 16 | 3601363 |
| 17 | -15487305 |
| 18 | 34949165 |
| 19 | -39821950 |
| 20 | 4356011 |
| 21 | 46881744 |
| 22 | -51274736 |
| 23 | 9005908 |
| 24 | 14663472 |
| 25 | -5205168 |
| 26 | -1456704 |
| 27 | -20736 |