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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 101 |
| 3 | 1101 |
| 4 | 10101 |
| 5 | 110101 |
| 6 | 1010101 |
| 7 | 11010101 |
| 8 | 101010101 |
| 9 | 1101010101 |
| 10 | 10101010101 |
| 11 | 110101010101 |
| 12 | 1010101010101 |
| 13 | 11010101010101 |
| 14 | 101010101010101 |
| 15 | 1101010101010101 |
| 16 | 10101010101010101 |
| 17 | 110101010101010101 |
| 18 | 1010101010101010101 |
| 19 | 11010101010101010101 |
[1,11,101,1101,10101,110101,1010101,11010101, 101010101,1101010101,10101010101,110101010101, 1010101010101,11010101010101,101010101010101, 1101010101010101,10101010101010101, 110101010101010101,1010101010101010101, 11010101010101010101] |