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 | -1 |
| 4 | -7 |
| 5 | 1 |
| 6 | -1 |
| 7 | 29 |
| 8 | -17 |
| 9 | 1 |
| 10 | -1 |
| 11 | -99 |
| 12 | 175 |
| 13 | -31 |
| 14 | 1 |
| 15 | -1 |
| 16 | 301 |
| 17 | -1425 |
| 18 | 569 |
| 19 | -49 |
| 20 | 1 |
| 21 | -1 |
| 22 | -851 |
| 23 | 10095 |
| 24 | -8071 |
| 25 | 1391 |
| 26 | -71 |
| 27 | 1 |
| 28 | -1 |
| 29 | 2285 |
| 30 | -65169 |
| 31 | 97769 |
| 32 | -29969 |
| 33 | 2869 |
| 34 | -97 |
| 35 | 1 |
| 36 | -1 |
| 37 | -5907 |
| 38 | 393583 |
| 39 | -1063447 |
| 40 | 543471 |
| 41 | -86731 |
| 42 | 5279 |
| 43 | -127 |
| 44 | 1 |
| 45 | -1 |
| 46 | 14829 |
| 47 | -2260625 |
| 48 | 10693865 |
| 49 | -8746257 |
| 50 | 2181269 |
| 51 | -212449 |
| 52 | 8945 |
| 53 | -161 |
| 54 | 1 |
| 55 | -1 |
| 56 | -36371 |
| 57 | 12484975 |
| 58 | -101280535 |
| 59 | 128879343 |
| 60 | -48218731 |
| 61 | 7045151 |
| 62 | -461455 |
| 63 | 14239 |
| 64 | -199 |
| 65 | 1 |