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 | 0 |
| 1 | 1 |
| 2 | 30 |
| 3 | 333 |
| 4 | 1444 |
| 5 | -570 |
| 6 | -21114 |
| 7 | -22576 |
| 8 | 121848 |
| 9 | 64233 |
| 10 | -276300 |
| 11 | 589260 |
| 12 | -1198764 |
| 13 | 133766 |
| 14 | -957216 |
| 15 | 2920590 |
| 16 | 2491792 |
| 17 | -1616958 |
| 18 | 1647054 |
| 19 | -5312428 |
| 20 | -14819880 |
| 21 | -4158576 |
| 22 | 20300904 |
| 23 | 16879848 |
| 24 | 19051416 |
| 25 | -22583225 |
| 26 | 38165172 |
| 27 | -81066987 |
| 28 | -47716288 |
| 29 | 66118494 |
| 30 | 370980 |
| 31 | -51834232 |