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 | -20 |
| 2 | 150 |
| 3 | -400 |
| 4 | -875 |
| 5 | 7396 |
| 6 | -7770 |
| 7 | -36600 |
| 8 | 56510 |
| 9 | 154660 |
| 10 | -872 |
| 11 | -1314200 |
| 12 | -455605 |
| 13 | 6284960 |
| 14 | 3781830 |
| 15 | -9954864 |
| 16 | -43558410 |
| 17 | -16664680 |
| 18 | 165132890 |
| 19 | 229738040 |
| 20 | 57372644 |
| 21 | -1326447180 |
| 22 | -2095012310 |
| 23 | 1723402120 |
| 24 | 7805180205 |