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 | 0 |
| 1 | -1 |
| 2 | 1 |
| 3 | -2 |
| 4 | 0 |
| 5 | 2 |
| 6 | -3 |
| 7 | -3 |
| 8 | 3 |
| 9 | 3 |
| 10 | -4 |
| 11 | -8 |
| 12 | 0 |
| 13 | 8 |
| 14 | 4 |
| 15 | -5 |
| 16 | -15 |
| 17 | -10 |
| 18 | 10 |
| 19 | 15 |
| 20 | 5 |
| 21 | -6 |
| 22 | -24 |
| 23 | -30 |
| 24 | 0 |
| 25 | 30 |
| 26 | 24 |
| 27 | 6 |
| 28 | -7 |
| 29 | -35 |
| 30 | -63 |
| 31 | -35 |
| 32 | 35 |
| 33 | 63 |
| 34 | 35 |
| 35 | 7 |
| 36 | -8 |
| 37 | -48 |
| 38 | -112 |
| 39 | -112 |
| 40 | 0 |
| 41 | 112 |
| 42 | 112 |
| 43 | 48 |
| 44 | 8 |
| 45 | -9 |
| 46 | -63 |
| 47 | -180 |
| 48 | -252 |
| 49 | -126 |
| 50 | 126 |
| 51 | 252 |
| 52 | 180 |
| 53 | 63 |
| 54 | 9 |
| 55 | -10 |
| 56 | -80 |
| 57 | -270 |
| 58 | -480 |
| 59 | -420 |
| 60 | 0 |
| 61 | 420 |
| 62 | 480 |
| 63 | 270 |
| 64 | 80 |
| 65 | 10 |