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 | 4 |
| 1 | 2 |
| 2 | 0 |
| 3 | -1 |
| 4 | 2 |
| 5 | -2 |
| 6 | 0 |
| 7 | 4 |
| 8 | -8 |
| 9 | 8 |
| 10 | 0 |
| 11 | -16 |
| 12 | 32 |
| 13 | -32 |
| 14 | -1 |
| 15 | 78 |
| 16 | -233 |
| 17 | 687 |
| 18 | -2363 |
| 19 | 8160 |
| 20 | -25670 |
| 21 | 72352 |
| 22 | -184451 |
| 23 | 430937 |
| 24 | -933087 |
| 25 | 1888690 |
| 26 | -3597221 |
| 27 | 6479696 |
| 28 | -11086920 |
| 29 | 18096128 |
| 30 | -28307626 |
| 31 | 42644791 |
| 32 | -62031001 |
| 33 | 86466285 |
| 34 | -110902034 |
| 35 | 110907489 |
| 36 | -52325 |
| 37 | -483682930 |