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 | 6 |
| 2 | 30 |
| 3 | 108 |
| 4 | 54 |
| 5 | -3564 |
| 6 | -41364 |
| 7 | -314280 |
| 8 | -1798362 |
| 9 | -6972156 |
| 10 | -1793340 |
| 11 | 283697640 |
| 12 | 3341429820 |
| 13 | 25984971720 |
| 14 | 151750943640 |
| 15 | 596184213168 |
| 16 | 101849014278 |
| 17 | -25747257110940 |
| 18 | -305001821608236 |
| 19 | -2392882855430328 |
| 20 | -14088646343199276 |
| 21 | -55649498057805096 |
| 22 | -7100681134947480 |