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 | 3 |
| 2 | -4 |
| 3 | 2 |
| 4 | -6 |
| 5 | -2 |
| 6 | -14 |
| 7 | -18 |
| 8 | -46 |
| 9 | -82 |
| 10 | -174 |
| 11 | -338 |
| 12 | -686 |
| 13 | -1362 |
| 14 | -2734 |
| 15 | -5458 |
| 16 | -10926 |
| 17 | -21842 |
| 18 | -43694 |
| 19 | -87378 |
| 20 | -174766 |
| 21 | -349522 |
| 22 | -699054 |
| 23 | -1398098 |
| 24 | -2796206 |
| 25 | -5592402 |
| 26 | -11184814 |
| 27 | -22369618 |
| 28 | -44739246 |
| 29 | -89478482 |
| 30 | -178956974 |
| 31 | -357913938 |
| 32 | -715827886 |