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 | 2 |
| 4 | 2 |
| 5 | -1 |
| 6 | 3 |
| 7 | 6 |
| 8 | -3 |
| 9 | -1 |
| 10 | 4 |
| 11 | 19 |
| 12 | 4 |
| 13 | -1 |
| 14 | 8 |
| 15 | 40 |
| 16 | -60 |
| 17 | -40 |
| 18 | 8 |
| 19 | 1 |
| 20 | 13 |
| 21 | 104 |
| 22 | -260 |
| 23 | -260 |
| 24 | 104 |
| 25 | 13 |
| 26 | -1 |
| 27 | 21 |
| 28 | 273 |
| 29 | -1092 |
| 30 | -1820 |
| 31 | 1092 |
| 32 | 273 |
| 33 | -21 |
| 34 | -1 |
| 35 | 33 |
| 36 | 747 |
| 37 | -3894 |
| 38 | -16270 |
| 39 | -3894 |
| 40 | 747 |
| 41 | 33 |
| 42 | -1 |
| 43 | 55 |
| 44 | 1870 |
| 45 | -19635 |
| 46 | -85085 |
| 47 | 136136 |
| 48 | 85085 |
| 49 | -19635 |
| 50 | -1870 |
| 51 | 55 |
| 52 | 1 |
| 53 | 89 |