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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 2 |
| 6 | -1 |
| 7 | 4 |
| 8 | 1 |
| 9 | 0 |
| 10 | 12 |
| 11 | 14 |
| 12 | -1 |
| 13 | 11 |
| 14 | -1 |
| 15 | -1 |
| 16 | 76 |
| 17 | 3 |
| 18 | 28 |
| 19 | -1 |
| 20 | 1 |
| 21 | 0 |
| 22 | 33 |
| 23 | -1 |
| 24 | -1 |
| 25 | 52 |
| 26 | 22 |
| 27 | 4 |
| 28 | 29 |
| 29 | 11 |
| 30 | 13 |
| 31 | 5 |
| 32 | -1 |
| 33 | -1 |
| 34 | 1 |
| 35 | 0 |
| 36 | 74 |
| 37 | -1 |
| 38 | 3 |
| 39 | -1 |
| 40 | 83 |
| 41 | -1 |
| 42 | -1 |
| 43 | 76 |
| 44 | 1006 |
| 45 | -1 |
| 46 | -1 |
| 47 | 518 |
| 48 | -1 |
| 49 | 150 |
| 50 | -1 |
| 51 | -1 |
| 52 | 103 |
| 53 | 133 |
| 54 | 51 |
| 55 | 14 |
| 56 | 45 |
| 57 | 19 |
| 58 | -1 |
| 59 | 5 |
| 60 | -1 |