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 | 0 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 8 |
| 6 | 11 |
| 7 | 101 |
| 8 | 141 |
| 9 | 161 |
| 10 | 181 |
| 11 | 1001 |
| 12 | 10001 |
| 13 | 10201 |
| 14 | 10401 |
| 15 | 10601 |
| 16 | 10801 |
| 17 | 100001 |
| 18 | 1000001 |
| 19 | 1002001 |
| 20 | 1004001 |
| 21 | 1006001 |
| 22 | 1008001 |
| 23 | 10000001 |
| 24 | 100000001 |
| 25 | 100020001 |
| 26 | 100040001 |
| 27 | 100060001 |
| 28 | 100080001 |
| 29 | 1000000001 |
| 30 | 10000000001 |