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 | 2 |
| 2 | -119 |
| 3 | -2160 |
| 4 | -16303 |
| 5 | -77882 |
| 6 | -279207 |
| 7 | -821356 |
| 8 | -2090591 |
| 9 | -4763286 |
| 10 | -9940951 |
| 11 | -19310024 |
| 12 | -35300367 |
| 13 | -61154194 |
| 14 | -100630535 |
| 15 | -156510468 |
| 16 | -225388735 |
| 17 | -281198510 |
| 18 | -224799543 |
| 19 | 268389728 |
| 20 | 2206784401 |