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 | 1 |
| 5 | -1 |
| 6 | 1 |
| 7 | 0 |
| 8 | -1 |
| 9 | 2 |
| 10 | -3 |
| 11 | 4 |
| 12 | -5 |
| 13 | 5 |
| 14 | -4 |
| 15 | 2 |
| 16 | 1 |
| 17 | -5 |
| 18 | 10 |
| 19 | -15 |
| 20 | 19 |
| 21 | -21 |
| 22 | 20 |
| 23 | -15 |
| 24 | 5 |
| 25 | 10 |
| 26 | -29 |
| 27 | 50 |
| 28 | -70 |
| 29 | 85 |
| 30 | -90 |
| 31 | 80 |
| 32 | -51 |
| 33 | 1 |
| 34 | 69 |
| 35 | -154 |
| 36 | 244 |
| 37 | -324 |
| 38 | 375 |
| 39 | -376 |
| 40 | 307 |
| 41 | -153 |
| 42 | -91 |
| 43 | 414 |
| 44 | -788 |
| 45 | 1163 |
| 46 | -1469 |
| 47 | 1621 |
| 48 | -1529 |
| 49 | 1115 |
| 50 | -328 |
| 51 | -833 |
| 52 | 2299 |
| 53 | -3916 |
| 54 | 5440 |
| 55 | -6550 |
| 56 | 6874 |
| 57 | -6039 |
| 58 | 3741 |
| 59 | 170 |
| 60 | -5600 |
| 61 | 12135 |
| 62 | -18990 |
| 63 | 25008 |