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 | 1 |
| 4 | -2 |
| 5 | 2 |
| 6 | -1 |
| 7 | 2 |
| 8 | -3 |
| 9 | 3 |
| 10 | -3 |
| 11 | 3 |
| 12 | -4 |
| 13 | 4 |
| 14 | -4 |
| 15 | 5 |
| 16 | -6 |
| 17 | 7 |
| 18 | -6 |
| 19 | 7 |
| 20 | -9 |
| 21 | 8 |
| 22 | -8 |
| 23 | 10 |
| 24 | -12 |
| 25 | 13 |
| 26 | -13 |
| 27 | 13 |
| 28 | -16 |
| 29 | 17 |
| 30 | -16 |
| 31 | 19 |
| 32 | -21 |
| 33 | 22 |
| 34 | -23 |
| 35 | 25 |
| 36 | -28 |
| 37 | 29 |
| 38 | -30 |
| 39 | 33 |
| 40 | -37 |
| 41 | 39 |
| 42 | -39 |
| 43 | 42 |
| 44 | -48 |
| 45 | 49 |
| 46 | -50 |
| 47 | 55 |
| 48 | -60 |
| 49 | 64 |
| 50 | -66 |
| 51 | 70 |
| 52 | -77 |
| 53 | 81 |
| 54 | -82 |
| 55 | 89 |
| 56 | -97 |
| 57 | 101 |
| 58 | -105 |
| 59 | 112 |
| 60 | -121 |
| 61 | 126 |
| 62 | -131 |
| 63 | 140 |
| 64 | -151 |
| 65 | 159 |
| 66 | -163 |
| 67 | 173 |
| 68 | -187 |
| 69 | 194 |
| 70 | -202 |