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 | 3 |
| 4 | -4 |
| 5 | 1 |
| 6 | -12 |
| 7 | 18 |
| 8 | -7 |
| 9 | 1 |
| 10 | 55 |
| 11 | -88 |
| 12 | 42 |
| 13 | -10 |
| 14 | 1 |
| 15 | -273 |
| 16 | 455 |
| 17 | -245 |
| 18 | 75 |
| 19 | -13 |
| 20 | 1 |
| 21 | 1428 |
| 22 | -2448 |
| 23 | 1428 |
| 24 | -510 |
| 25 | 117 |
| 26 | -16 |
| 27 | 1 |
| 28 | -7752 |
| 29 | 13566 |
| 30 | -8379 |
| 31 | 3325 |
| 32 | -910 |
| 33 | 168 |
| 34 | -19 |
| 35 | 1 |
| 36 | 43263 |
| 37 | -76912 |
| 38 | 49588 |
| 39 | -21252 |
| 40 | 6578 |
| 41 | -1472 |
| 42 | 228 |
| 43 | -22 |
| 44 | 1 |
| 45 | -246675 |
| 46 | 444015 |
| 47 | -296010 |
| 48 | 134550 |
| 49 | -45630 |
| 50 | 11700 |
| 51 | -2223 |
| 52 | 297 |
| 53 | -25 |
| 54 | 1 |