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 | -7 |
| 2 | 28 |
| 3 | -84 |
| 4 | 210 |
| 5 | -462 |
| 6 | 924 |
| 7 | -1714 |
| 8 | 2975 |
| 9 | -4795 |
| 10 | 6888 |
| 11 | -7616 |
| 12 | 1428 |
| 13 | 27132 |
| 14 | -116276 |
| 15 | 352632 |
| 16 | -919303 |
| 17 | 2180101 |
| 18 | -4815188 |
| 19 | 10010980 |
| 20 | -19650050 |
| 21 | 36268478 |
| 22 | -62075384 |
| 23 | 95196038 |
| 24 | -118778345 |
| 25 | 73332329 |
| 26 | 207719344 |
| 27 | -1138579904 |
| 28 | 3670243032 |
| 29 | -9852434200 |
| 30 | 23858720872 |