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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 101 |
| 4 | 111 |
| 5 | 1001 |
| 6 | 1111 |
| 7 | 10001 |
| 8 | 10101 |
| 9 | 11111 |
| 10 | 100001 |
| 11 | 111111 |
| 12 | 1000001 |
| 13 | 1001001 |
| 14 | 1010101 |
| 15 | 1111111 |
| 16 | 10000001 |
| 17 | 11111111 |
| 18 | 100000001 |
| 19 | 100010001 |
| 20 | 101010101 |
| 21 | 111111111 |
| 22 | 1000000001 |
| 23 | 1001001001 |
| 24 | 1111111111 |
| 25 | 10000000001 |
| 26 | 10000100001 |
| 27 | 10101010101 |
| 28 | 11111111111 |
[1,11,101,111,1001,1111,10001,10101,11111,100001, 111111,1000001,1001001,1010101,1111111,10000001, 11111111,100000001,100010001,101010101,111111111, 1000000001,1001001001,1111111111,10000000001, 10000100001,10101010101,11111111111] |