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 | 7 |
| 2 | 47 |
| 3 | 487 |
| 4 | 787 |
| 5 | 877 |
| 6 | 887 |
| 7 | 4447 |
| 8 | 4787 |
| 9 | 4877 |
| 10 | 7477 |
| 11 | 7487 |
| 12 | 7877 |
| 13 | 8447 |
| 14 | 8747 |
| 15 | 8887 |
| 16 | 44777 |
| 17 | 44887 |
| 18 | 47777 |
| 19 | 48487 |
| 20 | 48787 |
| 21 | 48847 |
| 22 | 74747 |
| 23 | 74887 |
| 24 | 77447 |
| 25 | 77477 |
| 26 | 77747 |
| 27 | 78487 |
| 28 | 78787 |
| 29 | 78877 |
| 30 | 78887 |
| 31 | 84787 |
| 32 | 87877 |
| 33 | 87887 |
| 34 | 88747 |
| 35 | 444487 |
| 36 | 444877 |
| 37 | 444887 |
| 38 | 447877 |
| 39 | 474787 |
| 40 | 474847 |