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 | 4 |
| 2 | 9 |
| 3 | 44 |
| 4 | 49 |
| 5 | 94 |
| 6 | 99 |
| 7 | 444 |
| 8 | 449 |
| 9 | 494 |
| 10 | 499 |
| 11 | 944 |
| 12 | 949 |
| 13 | 994 |
| 14 | 999 |
| 15 | 4444 |
| 16 | 4449 |
| 17 | 4494 |
| 18 | 4499 |
| 19 | 4944 |
| 20 | 4949 |
| 21 | 4994 |
| 22 | 4999 |
| 23 | 9444 |
| 24 | 9449 |
| 25 | 9494 |
| 26 | 9499 |
| 27 | 9944 |
| 28 | 9949 |
| 29 | 9994 |
| 30 | 9999 |
| 31 | 44444 |
| 32 | 44449 |
| 33 | 44494 |
| 34 | 44499 |
| 35 | 44944 |
| 36 | 44949 |
| 37 | 44994 |
| 38 | 44999 |
| 39 | 49444 |
| 40 | 49449 |
| 41 | 49494 |
| 42 | 49499 |
| 43 | 49944 |
| 44 | 49949 |