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 | 6 |
| 2 | 9 |
| 3 | 66 |
| 4 | 99 |
| 5 | 333 |
| 6 | 363 |
| 7 | 393 |
| 8 | 636 |
| 9 | 666 |
| 10 | 696 |
| 11 | 939 |
| 12 | 969 |
| 13 | 999 |
| 14 | 3333 |
| 15 | 3663 |
| 16 | 3993 |
| 17 | 6336 |
| 18 | 6666 |
| 19 | 6996 |
| 20 | 9339 |
| 21 | 9669 |
| 22 | 9999 |
| 23 | 30303 |
| 24 | 30603 |
| 25 | 30903 |
| 26 | 33333 |
| 27 | 33633 |
| 28 | 33933 |
| 29 | 36363 |
| 30 | 36663 |
| 31 | 36963 |
| 32 | 39393 |
| 33 | 39693 |
| 34 | 39993 |
| 35 | 60306 |
| 36 | 60606 |
| 37 | 60906 |
| 38 | 63336 |
| 39 | 63636 |
| 40 | 63936 |