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 | 0 |
| 2 | -60 |
| 3 | -80 |
| 4 | 1680 |
| 5 | 4704 |
| 6 | -25660 |
| 7 | -128640 |
| 8 | 150420 |
| 9 | 2062160 |
| 10 | 2230548 |
| 11 | -19194240 |
| 12 | -63712740 |
| 13 | 57664320 |
| 14 | 724837020 |
| 15 | 1055778256 |
| 16 | -3865916310 |
| 17 | -17164305600 |
| 18 | -7987686380 |
| 19 | 111558610080 |
| 20 | 309981082824 |
| 21 | -83708879920 |
| 22 | -2310552888780 |
| 23 | -4721178106560 |
| 24 | 4129349973890 |
| 25 | 39231750371520 |
| 26 | 64807106219940 |
| 27 | -86501225014320 |
| 28 | -580167287063160 |
| 29 | -840576756949440 |
| 30 | 1330114847500228 |