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| n | a(n) |
|---|---|
| 0 | 11 |
| 1 | 141 |
| 2 | 1441 |
| 3 | 14441 |
| 4 | 144441 |
| 5 | 1444441 |
| 6 | 14444441 |
| 7 | 144444441 |
| 8 | 1444444441 |
| 9 | 14444444441 |
| 10 | 144444444441 |
| 11 | 1444444444441 |
| 12 | 14444444444441 |
| 13 | 144444444444441 |
| 14 | 1444444444444441 |
| 15 | 14444444444444441 |
| 16 | 144444444444444441 |
| 17 | 1444444444444444441 |
| 18 | 14444444444444444441 |
[11,141,1441,14441,144441,1444441,14444441, 144444441,1444444441,14444444441,144444444441, 1444444444441,14444444444441,144444444444441, 1444444444444441,14444444444444441, 144444444444444441,1444444444444444441, 14444444444444444441] |