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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 601 |
| 6 | 21001 |
| 7 | 60100001 |
| 8 | 2100100000001 |
| 9 | 601000010000000000001 |
| 10 | 2100100000001000000000000000000001 |
| 11 | 6010000100000000000010000000000000000000000000000000001 |
[1,2,6,21,601,21001,60100001,2100100000001, 601000010000000000001, 2100100000001000000000000000000001, 60100001000000000000100000000000000000000000000000\ 00001] |