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 | -25 |
| 2 | 300 |
| 3 | -2300 |
| 4 | 12650 |
| 5 | -53130 |
| 6 | 177100 |
| 7 | -480700 |
| 8 | 1081575 |
| 9 | -2042975 |
| 10 | 3268760 |
| 11 | -4457400 |
| 12 | 5200300 |
| 13 | -5200300 |
| 14 | 4457400 |
| 15 | -3268760 |
| 16 | 2042975 |
| 17 | -1081575 |
| 18 | 480700 |
| 19 | -177100 |
| 20 | 53130 |
| 21 | -12650 |
| 22 | 2300 |
| 23 | -300 |
| 24 | 25 |