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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 32 |
| 4 | 182 |
| 5 | 1117 |
| 6 | 7280 |
| 7 | 49625 |
| 8 | 349998 |
| 9 | 2535077 |
| 10 | 18758264 |
| 11 | 141254654 |
| 12 | 1079364104 |
| 13 | 8350678169 |
| 14 | 65298467486 |
| 15 | 515349097712 |
| 16 | 4100346740510 |
| 17 | 32858696386765 |
| 18 | 265001681344568 |
| 19 | 2149447880547398 |
| 20 | 17524254766905368 |
| 21 | 143540915998174577 |
| 22 | 1180736721910617182 |
[1,6,32,182,1117,7280,49625,349998,2535077, 18758264,141254654,1079364104,8350678169, 65298467486,515349097712,4100346740510, 32858696386765,265001681344568,2149447880547398, 17524254766905368,143540915998174577, 1180736721910617182] |