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 | 0 |
| 1 | 2 |
| 2 | -1 |
| 3 | 6 |
| 4 | -3 |
| 5 | 16 |
| 6 | -8 |
| 7 | 42 |
| 8 | -21 |
| 9 | 110 |
| 10 | -55 |
| 11 | 288 |
| 12 | -144 |
| 13 | 754 |
| 14 | -377 |
| 15 | 1974 |
| 16 | -987 |
| 17 | 5168 |
| 18 | -2584 |
| 19 | 13530 |
| 20 | -6765 |
| 21 | 35422 |
| 22 | -17711 |
| 23 | 92736 |
| 24 | -46368 |
| 25 | 242786 |
| 26 | -121393 |
| 27 | 635622 |
| 28 | -317811 |
| 29 | 1664080 |
| 30 | -832040 |
| 31 | 4356618 |
| 32 | -2178309 |
| 33 | 11405774 |
| 34 | -5702887 |
| 35 | 29860704 |
| 36 | -14930352 |
| 37 | 78176338 |