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 | -3 |
| 2 | 9 |
| 3 | -24 |
| 4 | 57 |
| 5 | -126 |
| 6 | 264 |
| 7 | -528 |
| 8 | 1017 |
| 9 | -1896 |
| 10 | 3438 |
| 11 | -6084 |
| 12 | 10536 |
| 13 | -17898 |
| 14 | 29880 |
| 15 | -49104 |
| 16 | 79545 |
| 17 | -127170 |
| 18 | 200856 |
| 19 | -313692 |
| 20 | 484830 |
| 21 | -742080 |
| 22 | 1125540 |
| 23 | -1692648 |
| 24 | 2525160 |
| 25 | -3738765 |
| 26 | 5496246 |
| 27 | -8025432 |
| 28 | 11643576 |
| 29 | -16790310 |
| 30 | 24072048 |
| 31 | -34321560 |
| 32 | 48677625 |