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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 9 |
| 5 | 36 |
| 6 | 162 |
| 7 | 900 |
| 8 | 5616 |
| 9 | 33048 |
| 10 | 178459 |
| 11 | 940896 |
| 12 | 5038848 |
| 13 | 27546779 |
| 14 | 153264960 |
| 15 | 863910489 |
| 16 | 4897760256 |
| 17 | 27770211072 |
| 18 | 157340548224 |
| 19 | 892526107392 |
| 20 | 5077739844402 |
| 21 | 28988793435209 |
| 22 | 166026726038016 |
| 23 | 953309368018944 |
| 24 | 5484237660094464 |
| 25 | 31597040041716690 |
[1,2,3,9,36,162,900,5616,33048,178459,940896, 5038848,27546779,153264960,863910489,4897760256, 27770211072,157340548224,892526107392, 5077739844402,28988793435209,166026726038016, 953309368018944,5484237660094464, 31597040041716690] |