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 | 0 |
| 3 | -1 |
| 4 | 1 |
| 5 | -1 |
| 6 | 1 |
| 7 | -2 |
| 8 | 3 |
| 9 | -2 |
| 10 | 3 |
| 11 | -3 |
| 12 | 4 |
| 13 | -4 |
| 14 | 4 |
| 15 | -6 |
| 16 | 7 |
| 17 | -7 |
| 18 | 7 |
| 19 | -9 |
| 20 | 10 |
| 21 | -12 |
| 22 | 13 |
| 23 | -14 |
| 24 | 17 |
| 25 | -18 |
| 26 | 19 |
| 27 | -22 |
| 28 | 26 |
| 29 | -28 |
| 30 | 29 |
| 31 | -34 |
| 32 | 38 |
| 33 | -41 |
| 34 | 44 |
| 35 | -50 |
| 36 | 57 |
| 37 | -60 |
| 38 | 65 |
| 39 | -72 |
| 40 | 81 |
| 41 | -86 |
| 42 | 94 |
| 43 | -105 |
| 44 | 114 |
| 45 | -124 |
| 46 | 133 |
| 47 | -146 |
| 48 | 161 |
| 49 | -174 |
| 50 | 187 |
| 51 | -204 |
| 52 | 224 |
| 53 | -240 |
| 54 | 258 |
| 55 | -282 |
| 56 | 309 |
| 57 | -332 |
| 58 | 354 |
| 59 | -386 |
| 60 | 419 |
| 61 | -450 |
| 62 | 481 |
| 63 | -524 |
| 64 | 569 |
| 65 | -606 |
| 66 | 651 |
| 67 | -703 |