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 | 0 |
| 4 | 0 |
| 5 | -1 |
| 6 | -1 |
| 7 | 0 |
| 8 | 1 |
| 9 | 2 |
| 10 | 1 |
| 11 | 0 |
| 12 | -2 |
| 13 | -3 |
| 14 | -2 |
| 15 | 0 |
| 16 | 3 |
| 17 | 4 |
| 18 | 4 |
| 19 | 0 |
| 20 | -4 |
| 21 | -6 |
| 22 | -5 |
| 23 | 0 |
| 24 | 5 |
| 25 | 9 |
| 26 | 6 |
| 27 | 0 |
| 28 | -8 |
| 29 | -12 |
| 30 | -9 |
| 31 | 0 |
| 32 | 12 |
| 33 | 16 |
| 34 | 13 |
| 35 | 0 |
| 36 | -14 |
| 37 | -22 |
| 38 | -17 |
| 39 | 0 |
| 40 | 18 |
| 41 | 29 |
| 42 | 21 |
| 43 | 0 |
| 44 | -26 |
| 45 | -38 |
| 46 | -28 |
| 47 | 0 |
| 48 | 34 |
| 49 | 50 |
| 50 | 39 |
| 51 | 0 |
| 52 | -42 |
| 53 | -64 |
| 54 | -49 |
| 55 | 0 |
| 56 | 53 |
| 57 | 82 |
| 58 | 60 |
| 59 | 0 |
| 60 | -70 |
| 61 | -105 |
| 62 | -78 |
| 63 | 0 |
| 64 | 90 |
| 65 | 132 |
| 66 | 101 |
| 67 | 0 |
| 68 | -110 |
| 69 | -166 |
| 70 | -125 |
| 71 | 0 |
| 72 | 137 |
| 73 | 208 |
| 74 | 153 |
| 75 | 0 |
| 76 | -174 |
| 77 | -258 |
| 78 | -192 |
| 79 | 0 |
| 80 | 217 |