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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 11 |
| 2 | 13 |
| 3 | 141 |
| 4 | 143 |
| 5 | 1441 |
| 6 | 1443 |
| 7 | 14441 |
| 8 | 14443 |
| 9 | 144441 |
| 10 | 144443 |
| 11 | 1444441 |
| 12 | 1444443 |
| 13 | 14444441 |
| 14 | 14444443 |
| 15 | 144444441 |
| 16 | 144444443 |
| 17 | 1444444441 |
| 18 | 1444444443 |
| 19 | 14444444441 |
| 20 | 14444444443 |
| 21 | 144444444441 |
| 22 | 144444444443 |
| 23 | 1444444444441 |
[0,11,13,141,143,1441,1443,14441,14443,144441, 144443,1444441,1444443,14444441,14444443, 144444441,144444443,1444444441,1444444443, 14444444441,14444444443,144444444441,144444444443, 1444444444441] |