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) |
|---|---|
| 1 | 0 |
| 2 | -1728 |
| 3 | 3375 |
| 4 | -8000 |
| 5 | 32768 |
| 6 | -54000 |
| 7 | -121287375 |
| 8 | -287496 |
| 9 | 884736 |
| 10 | -681472000 |
| 11 | 12771880859375 |
| 12 | 14670139392 |
| 13 | 12288000 |
| 14 | -16581375 |
| 15 | 1566028350940383 |
| 16 | 12167000000 |
| 17 | -134217728000 |
| 18 | -1790957481984 |
| 19 | 20919104368024767633 |
| 20 | 9103145472000 |
| 21 | 884736000 |