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 | -5 |
| 2 | 0 |
| 3 | 25 |
| 4 | 0 |
| 5 | -26 |
| 6 | -145 |
| 7 | 0 |
| 8 | 265 |
| 9 | 265 |
| 10 | 993 |
| 11 | -825 |
| 12 | -2070 |
| 13 | -3190 |
| 14 | -2335 |
| 15 | 2739 |
| 16 | 7890 |
| 17 | 29570 |
| 18 | 21085 |
| 19 | -5250 |
| 20 | -73006 |
| 21 | -71945 |
| 22 | -191140 |
| 23 | -176805 |
| 24 | 185045 |
| 25 | 295675 |
| 26 | 1204590 |
| 27 | 1067375 |
| 28 | 1353655 |
| 29 | -910885 |
| 30 | -3688009 |
| 31 | -4645850 |
| 32 | -9409195 |
| 33 | -12021485 |
| 34 | -4296815 |
| 35 | 19981183 |
| 36 | 28942560 |
| 37 | 76843230 |
| 38 | 70996895 |