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 | -1 |
| 3 | 1 |
| 4 | 2 |
| 5 | -2 |
| 6 | -2 |
| 7 | 5 |
| 8 | 2 |
| 9 | -9 |
| 10 | 1 |
| 11 | 16 |
| 12 | -8 |
| 13 | -24 |
| 14 | 25 |
| 15 | 32 |
| 16 | -57 |
| 17 | -31 |
| 18 | 114 |
| 19 | 6 |
| 20 | -202 |
| 21 | 77 |
| 22 | 322 |
| 23 | -273 |
| 24 | -447 |
| 25 | 672 |
| 26 | 496 |
| 27 | -1392 |
| 28 | -271 |
| 29 | 2560 |
| 30 | -625 |
| 31 | -4223 |
| 32 | 2914 |
| 33 | 6158 |
| 34 | -7762 |
| 35 | -7467 |
| 36 | 16834 |
| 37 | 5863 |
| 38 | -32063 |
| 39 | 3504 |
| 40 | 54760 |
| 41 | -29704 |
| 42 | -83319 |
| 43 | 87968 |
| 44 | 108375 |
| 45 | -200991 |
| 46 | -103726 |
| 47 | 397334 |
| 48 | 11110 |
| 49 | -702051 |
| 50 | 282498 |
| 51 | 1110495 |