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 | -1 |
| 3 | -2 |
| 4 | 0 |
| 5 | 0 |
| 6 | -3 |
| 7 | 1 |
| 8 | 8 |
| 9 | 1 |
| 10 | 1 |
| 11 | 26 |
| 12 | 7 |
| 13 | -51 |
| 14 | -3 |
| 15 | 0 |
| 16 | -264 |
| 17 | -186 |
| 18 | 348 |
| 19 | -120 |
| 20 | -285 |
| 21 | 2697 |
| 22 | 2871 |
| 23 | -2304 |
| 24 | 3393 |
| 25 | 8029 |
| 26 | -25795 |
| 27 | -36872 |
| 28 | 16108 |
| 29 | -60010 |
| 30 | -159683 |
| 31 | 213795 |
| 32 | 413712 |
| 33 | -181857 |
| 34 | 833779 |
| 35 | 2669534 |
| 36 | -1272977 |
| 37 | -4030235 |
| 38 | 3611168 |
| 39 | -9145271 |
| 40 | -39467427 |