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 | 2 |
| 3 | -2 |
| 4 | 4 |
| 5 | -7 |
| 6 | 10 |
| 7 | -19 |
| 8 | 27 |
| 9 | -49 |
| 10 | 73 |
| 11 | -126 |
| 12 | 195 |
| 13 | -326 |
| 14 | 516 |
| 15 | -848 |
| 16 | 1358 |
| 17 | -2213 |
| 18 | 3564 |
| 19 | -5785 |
| 20 | 9341 |
| 21 | -15135 |
| 22 | 24467 |
| 23 | -39612 |
| 24 | 64069 |
| 25 | -103692 |
| 26 | 167750 |
| 27 | -271454 |
| 28 | 439192 |
| 29 | -710659 |
| 30 | 1149838 |
| 31 | -1860511 |
| 32 | 3010335 |
| 33 | -4870861 |
| 34 | 7881181 |
| 35 | -12752058 |
| 36 | 20633223 |
| 37 | -33385298 |
| 38 | 54018504 |
| 39 | -87403820 |
| 40 | 141422306 |