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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 61 |
| 6 | 221 |
| 7 | 442 |
| 8 | 884 |
| 9 | 8761 |
| 10 | 75221 |
| 11 | 544210 |
| 12 | 8842100 |
| 13 | 87642100 |
| 14 | 875422100 |
| 15 | 8754421000 |
| 16 | 88754210000 |
| 17 | 877542100000 |
| 18 | 8755421000000 |
| 19 | 87542110000000 |
| 20 | 875422100000000 |
| 21 | 8754421000000000 |
| 22 | 88754210000000000 |
| 23 | 877542100000000000 |
| 24 | 8755421000000000000 |
[1,2,4,8,61,221,442,884,8761,75221,544210,8842100, 87642100,875422100,8754421000,88754210000, 877542100000,8755421000000,87542110000000, 875422100000000,8754421000000000, 88754210000000000,877542100000000000, 8755421000000000000] |