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 | 3 |
| 3 | 91 |
| 4 | 193131 |
| 5 | 9939111 |
| 6 | 119993391339919111 |
| 7 | 199913191913191191 |
| 8 | 399139119131339931 |
| 9 | 139191313119199339131 |
| 10 | 1313933311991311991139331 |
| 11 | 3131199393919119319199931 |
| 12 | 31313993393319311993391131311 |
| 13 | 1191131333139133131313199933931 |