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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 9 |
| 3 | 45 |
| 4 | 441 |
| 5 | 3645 |
| 6 | 31329 |
| 7 | 266805 |
| 8 | 2277081 |
| 9 | 19424205 |
| 10 | 165714129 |
| 11 | 1413721125 |
| 12 | 12060652041 |
| 13 | 102890947005 |
| 14 | 877775988609 |
| 15 | 7488419962005 |
| 16 | 63884675998521 |
| 17 | 545008403548845 |
| 18 | 4649536929125169 |
| 19 | 39665798745571845 |
| 20 | 338394040998364521 |
[0,9,45,441,3645,31329,266805,2277081,19424205, 165714129,1413721125,12060652041,102890947005, 877775988609,7488419962005,63884675998521, 545008403548845,4649536929125169, 39665798745571845,338394040998364521] |