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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 153 |
| 3 | 2737 |
| 4 | 49105 |
| 5 | 881145 |
| 6 | 15811497 |
| 7 | 283725793 |
| 8 | 5091252769 |
| 9 | 91358824041 |
| 10 | 1639367579961 |
| 11 | 29417257615249 |
| 12 | 527871269494513 |
| 13 | 9472265593285977 |
| 14 | 169972909409653065 |
| 15 | 3050040103780469185 |
| 16 | 54730748958638792257 |
| 17 | 982103441151717791433 |
| 18 | 17623131191772281453529 |
| 19 | 316234258010749348372081 |
| 20 | 5674593513001715989243921 |
[1,9,153,2737,49105,881145,15811497,283725793, 5091252769,91358824041,1639367579961, 29417257615249,527871269494513,9472265593285977, 169972909409653065,3050040103780469185, 54730748958638792257,982103441151717791433, 17623131191772281453529,316234258010749348372081, 5674593513001715989243921] |