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 | -1 |
| 2 | -2 |
| 3 | 0 |
| 4 | 5 |
| 5 | 1 |
| 6 | -12 |
| 7 | -3 |
| 8 | 31 |
| 9 | 13 |
| 10 | -64 |
| 11 | -57 |
| 12 | 139 |
| 13 | 164 |
| 14 | -285 |
| 15 | -458 |
| 16 | 560 |
| 17 | 1217 |
| 18 | -950 |
| 19 | -3176 |
| 20 | 1396 |
| 21 | 7786 |
| 22 | -1129 |
| 23 | -18607 |
| 24 | -2378 |
| 25 | 43043 |
| 26 | 17680 |
| 27 | -96655 |
| 28 | -67957 |
| 29 | 208061 |
| 30 | 217269 |
| 31 | -429510 |
| 32 | -628868 |
| 33 | 836424 |
| 34 | 1710935 |
| 35 | -1497065 |
| 36 | -4434111 |
| 37 | 2294633 |
| 38 | 11061661 |
| 39 | -2348910 |