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) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | -3 |
| 4 | 0 |
| 5 | -5 |
| 6 | 6 |
| 7 | -9 |
| 8 | 0 |
| 9 | 2 |
| 10 | 10 |
| 11 | -17 |
| 12 | 0 |
| 13 | -33 |
| 14 | 18 |
| 15 | 19 |
| 16 | 0 |
| 17 | -65 |
| 18 | -4 |
| 19 | -129 |
| 20 | 0 |
| 21 | 35 |
| 22 | 34 |
| 23 | -257 |
| 24 | 0 |
| 25 | 12 |
| 26 | 66 |
| 27 | 0 |
| 28 | 0 |
| 29 | -513 |
| 30 | -38 |
| 31 | -1025 |
| 32 | 0 |
| 33 | 67 |
| 34 | 130 |
| 35 | 69 |
| 36 | 0 |
| 37 | -2049 |
| 38 | 258 |
| 39 | 131 |
| 40 | 0 |
| 41 | -4097 |
| 42 | -70 |
| 43 | -8193 |
| 44 | 0 |
| 45 | -22 |
| 46 | 514 |
| 47 | -16385 |
| 48 | 0 |
| 49 | 56 |
| 50 | -24 |
| 51 | 259 |
| 52 | 0 |
| 53 | -32769 |
| 54 | 0 |
| 55 | 133 |
| 56 | 0 |
| 57 | 515 |
| 58 | 1026 |
| 59 | -65537 |
| 60 | 0 |
| 61 | -131073 |
| 62 | 2050 |
| 63 | -42 |
| 64 | 0 |
| 65 | 261 |
| 66 | -134 |
| 67 | -262145 |
| 68 | 0 |
| 69 | 1027 |