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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 73 |
| 3 | 536 |
| 4 | 3590 |
| 5 | 22162 |
| 6 | 127604 |
| 7 | 693552 |
| 8 | 3598120 |
| 9 | 17990600 |
| 10 | 87396728 |
| 11 | 413977192 |
| 12 | 1918222840 |
| 13 | 8719846960 |
| 14 | 38983643908 |
| 15 | 171764779170 |
| 16 | 747190081890 |
| 17 | 3213760467348 |
| 18 | 13684132415133 |
| 19 | 57742830924831 |
| 20 | 241687792906641 |
[9,73,536,3590,22162,127604,693552,3598120, 17990600,87396728,413977192,1918222840,8719846960, 38983643908,171764779170,747190081890, 3213760467348,13684132415133,57742830924831, 241687792906641] |