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 | 91 |
| 2 | 990 |
| 3 | 199396 |
| 4 | 998991 |
| 5 | 399949903 |
| 6 | 2919969990 |
| 7 | 39999939903 |
| 8 | 999999911791 |
| 9 | 9999192996990 |
| 10 | 499798990999990 |
| 11 | 99597939989199996 |
| 12 | 999699998689998991 |
| 13 | 19699899919999499091 |
| 14 | 999532899999499099996 |
| 15 | 999999859999976929990 |
| 16 | 199793999409939999989991 |
| 17 | 138999999499599999199995 |
| 18 | 99996999694999999299662991 |