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 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 0 |
| 6 | -1 |
| 7 | 2 |
| 8 | 1 |
| 9 | 0 |
| 10 | 3 |
| 11 | -3 |
| 12 | 3 |
| 13 | 1 |
| 14 | 0 |
| 15 | -15 |
| 16 | 12 |
| 17 | -6 |
| 18 | 4 |
| 19 | 1 |
| 20 | 0 |
| 21 | 105 |
| 22 | -75 |
| 23 | 30 |
| 24 | -10 |
| 25 | 5 |
| 26 | 1 |
| 27 | 0 |
| 28 | -945 |
| 29 | 630 |
| 30 | -225 |
| 31 | 60 |
| 32 | -15 |
| 33 | 6 |
| 34 | 1 |
| 35 | 0 |
| 36 | 10395 |
| 37 | -6615 |
| 38 | 2205 |
| 39 | -525 |
| 40 | 105 |
| 41 | -21 |
| 42 | 7 |
| 43 | 1 |
| 44 | 0 |
| 45 | -135135 |
| 46 | 83160 |
| 47 | -26460 |
| 48 | 5880 |
| 49 | -1050 |
| 50 | 168 |
| 51 | -28 |
| 52 | 8 |
| 53 | 1 |
| 54 | 0 |
| 55 | 2027025 |
| 56 | -1216215 |
| 57 | 374220 |
| 58 | -79380 |