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 | -1 |
| 3 | 0 |
| 4 | -1 |
| 5 | -1 |
| 6 | 0 |
| 7 | 0 |
| 8 | -1 |
| 9 | -2 |
| 10 | 1 |
| 11 | -2 |
| 12 | 1 |
| 13 | -2 |
| 14 | 1 |
| 15 | -1 |
| 16 | 1 |
| 17 | -5 |
| 18 | 4 |
| 19 | -8 |
| 20 | 7 |
| 21 | -10 |
| 22 | 9 |
| 23 | -13 |
| 24 | 12 |
| 25 | -15 |
| 26 | 15 |
| 27 | -19 |
| 28 | 26 |
| 29 | -28 |
| 30 | 27 |
| 31 | -30 |
| 32 | 29 |
| 33 | -34 |
| 34 | 41 |
| 35 | -66 |
| 36 | 66 |
| 37 | -100 |
| 38 | 99 |
| 39 | -163 |
| 40 | 170 |
| 41 | -223 |
| 42 | 222 |
| 43 | -323 |
| 44 | 322 |
| 45 | -420 |
| 46 | 453 |
| 47 | -622 |
| 48 | 621 |
| 49 | -771 |
| 50 | 770 |
| 51 | -997 |
| 52 | 1121 |
| 53 | -1363 |
| 54 | 1362 |
| 55 | -1851 |
| 56 | 1883 |
| 57 | -2562 |
| 58 | 3073 |
| 59 | -3857 |
| 60 | 3856 |