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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 112 |
| 4 | 1122 |
| 5 | 11222 |
| 6 | 112222 |
| 7 | 1122220 |
| 8 | 11222202 |
| 9 | 112222021 |
| 10 | 1122220211 |
| 11 | 11222202111 |
| 12 | 112222021110 |
| 13 | 1122220211102 |
| 14 | 11222202111020 |
| 15 | 112222021110202 |
| 16 | 1122220211102020 |
| 17 | 11222202111020201 |
| 18 | 112222021110202010 |
| 19 | 1122220211102020102 |
| 20 | 11222202111020201022 |
| 21 | 112222021110202010220 |
[1,11,112,1122,11222,112222,1122220,11222202, 112222021,1122220211,11222202111,112222021110, 1122220211102,11222202111020,112222021110202, 1122220211102020,11222202111020201, 112222021110202010,1122220211102020102, 11222202111020201022,112222021110202010220] |