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 | 300 |
| 3 | -2325 |
| 4 | 13275 |
| 5 | -60655 |
| 6 | 235525 |
| 7 | -811975 |
| 8 | 2558575 |
| 9 | -7502175 |
| 10 | 20713560 |
| 11 | -54345175 |
| 12 | 136483700 |
| 13 | -329961200 |
| 14 | 771284950 |
| 15 | -1749490965 |
| 16 | 3862641850 |
| 17 | -8322360350 |
| 18 | 17536187475 |
| 19 | -36204137625 |
| 20 | 73353404555 |
| 21 | -146061623800 |
| 22 | 286183499350 |
| 23 | -552361219950 |
| 24 | 1051231017350 |