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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 100 |
| 3 | 111 |
| 4 | 10000 |
| 5 | 11111 |
| 6 | 1100000 |
| 7 | 111111 |
| 8 | 110000000 |
| 9 | 11111111 |
| 10 | 11000000000 |
| 11 | 1111111111 |
| 12 | 1100000000000 |
| 13 | 111111111111 |
| 14 | 111100000000000 |
| 15 | 111111111111 |
| 16 | 11110000000000000 |
| 17 | 11111111111111 |
| 18 | 1111000000000000000 |
| 19 | 1111111111111111 |
| 20 | 111100000000000000000 |
[1,11,100,111,10000,11111,1100000,111111, 110000000,11111111,11000000000,1111111111, 1100000000000,111111111111,111100000000000, 111111111111,11110000000000000,11111111111111, 1111000000000000000,1111111111111111, 111100000000000000000] |