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 | 10 |
| 3 | 91 |
| 4 | 190 |
| 5 | 990 |
| 6 | 10011 |
| 7 | 19110 |
| 8 | 19900 |
| 9 | 90100 |
| 10 | 1911990 |
| 11 | 1991010 |
| 12 | 1999000 |
| 13 | 99991011 |
| 14 | 199110990 |
| 15 | 199910010 |
| 16 | 199990000 |
| 17 | 901999101 |
| 18 | 1000900911 |
| 19 | 1111019091 |
| 20 | 19991100990 |
| 21 | 19999100010 |
| 22 | 19999900000 |
| 23 | 1999911000990 |
| 24 | 1999991000010 |
| 25 | 1999999000000 |
| 26 | 11109109109010 |