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 | -25 |
| 2 | 675 |
| 3 | -19575 |
| 4 | 606225 |
| 5 | -19944225 |
| 6 | 693835875 |
| 7 | -25422933375 |
| 8 | 977745218625 |
| 9 | -39350424479625 |
| 10 | 1652904664495875 |
| 11 | -72294275991774375 |
| 12 | 3285576793503860625 |
| 13 | -154866859897225100625 |
| 14 | 7558086937740656191875 |
| 15 | -381335852895175582779375 |