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 | 2 |
| 3 | -1 |
| 4 | 3 |
| 5 | 1 |
| 6 | 12 |
| 7 | 1 |
| 8 | 30 |
| 9 | -1 |
| 10 | 35 |
| 11 | 1 |
| 12 | 56 |
| 13 | 1 |
| 14 | 90 |
| 15 | -1 |
| 16 | 99 |
| 17 | 1 |
| 18 | 132 |
| 19 | 1 |
| 20 | 182 |
| 21 | -1 |
| 22 | 195 |
| 23 | 1 |
| 24 | 240 |
| 25 | 1 |
| 26 | 306 |
| 27 | -1 |
| 28 | 323 |
| 29 | 1 |
| 30 | 380 |
| 31 | 1 |
| 32 | 462 |
| 33 | -1 |
| 34 | 483 |
| 35 | 1 |
| 36 | 552 |
| 37 | 1 |
| 38 | 650 |
| 39 | -1 |
| 40 | 675 |
| 41 | 1 |
| 42 | 756 |
| 43 | 1 |
| 44 | 870 |
| 45 | -1 |
| 46 | 899 |
| 47 | 1 |
| 48 | 992 |
| 49 | 1 |
| 50 | 1122 |
| 51 | -1 |
| 52 | 1155 |
| 53 | 1 |