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) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 201 |
| 3 | 3001 |
| 4 | 40001 |
| 5 | 500001 |
| 6 | 6000001 |
| 7 | 70000001 |
| 8 | 800000001 |
| 9 | 9000000001 |
| 10 | 100000000001 |
| 11 | 1100000000001 |
| 12 | 12000000000001 |
| 13 | 130000000000001 |
| 14 | 1400000000000001 |
| 15 | 15000000000000001 |
| 16 | 160000000000000001 |
| 17 | 1700000000000000001 |
| 18 | 18000000000000000001 |
| 19 | 190000000000000000001 |