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 | 60 |
| 2 | -4860 |
| 3 | 660480 |
| 4 | -105063420 |
| 5 | 18206269560 |
| 6 | -3328461434880 |
| 7 | 631226199152640 |
| 8 | -122944850563477500 |
| 9 | 24436796345920143420 |
| 10 | -4935178772322020730360 |
| 11 | 1009598430837232126725120 |
| 12 | -208736157503462405753487360 |
| 13 | 43541664791244563211024015480 |