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 | 91 |
| 3 | 171 |
| 4 | 1711 |
| 5 | 171991 |
| 6 | 791911 |
| 7 | 1717771191 |
| 8 | 911977119991 |
| 9 | 999999911791 |
| 10 | 1771177919779971 |
| 11 | 977779999771199191 |
| 12 | 17979999719799917971 |
| 13 | 7197199171171779119991779991 |