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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 2211 |
| 3 | 222111 |
| 4 | 22221111 |
| 5 | 2222211111 |
| 6 | 222222111111 |
| 7 | 22222221111111 |
| 8 | 2222222211111111 |
| 9 | 222222222111111111 |
| 10 | 22222222221111111111 |
| 11 | 2222222222211111111111 |
| 12 | 222222222222111111111111 |
| 13 | 22222222222221111111111111 |
| 14 | 2222222222222211111111111111 |
| 15 | 222222222222222111111111111111 |
| 16 | 22222222222222221111111111111111 |
[21,2211,222111,22221111,2222211111,222222111111, 22222221111111,2222222211111111, 222222222111111111,22222222221111111111, 2222222222211111111111,222222222222111111111111, 22222222222221111111111111, 2222222222222211111111111111, 222222222222222111111111111111, 22222222222222221111111111111111] |