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| n | a(n) |
|---|---|
| 1 | 11 |
| 2 | 45 |
| 3 | 185 |
| 4 | 820 |
| 5 | 4450 |
| 6 | 21472 |
| 7 | 117959 |
| 8 | 653280 |
| 9 | 3702873 |
| 10 | 21843997 |
| 11 | 128432043 |
| 12 | 772854026 |
| 13 | 4670530787 |
| 14 | 28365620848 |
| 15 | 173414566634 |
| 16 | 1061055576890 |
| 17 | 6512490329181 |
| 18 | 40022336748789 |
| 19 | 246149226462653 |
| 20 | 1515462897926857 |
[11,45,185,820,4450,21472,117959,653280,3702873, 21843997,128432043,772854026,4670530787, 28365620848,173414566634,1061055576890, 6512490329181,40022336748789,246149226462653, 1515462897926857] |