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 | 0 |
| 2 | 0 |
| 3 | -2 |
| 4 | -4 |
| 5 | -8 |
| 6 | -12 |
| 7 | -16 |
| 8 | -16 |
| 9 | -8 |
| 10 | 16 |
| 11 | 64 |
| 12 | 144 |
| 13 | 256 |
| 14 | 384 |
| 15 | 480 |
| 16 | 448 |
| 17 | 128 |
| 18 | -704 |
| 19 | -2304 |
| 20 | -4864 |
| 21 | -8320 |
| 22 | -12032 |
| 23 | -14336 |
| 24 | -12032 |
| 25 | 0 |
| 26 | 28672 |
| 27 | 81408 |
| 28 | 162816 |
| 29 | 268288 |
| 30 | 373760 |
| 31 | 421888 |
| 32 | 307200 |
| 33 | -133120 |
| 34 | -1110016 |
| 35 | -2834432 |
| 36 | -5402624 |
| 37 | -8585216 |
| 38 | -11501568 |
| 39 | -12197888 |