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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 35 |
| 4 | 219 |
| 5 | 1594 |
| 6 | 12935 |
| 7 | 113945 |
| 8 | 1070324 |
| 9 | 10586856 |
| 10 | 109259633 |
| 11 | 1168384157 |
| 12 | 12877168147 |
| 13 | 145656436074 |
| 14 | 1685157199175 |
| 15 | 19886174611045 |
| 16 | 238819338399054 |
| 17 | 2913166800256664 |
| 18 | 36036122671902718 |
| 19 | 451429953643336590 |
| 20 | 5720172601392931006 |
[2,7,35,219,1594,12935,113945,1070324,10586856, 109259633,1168384157,12877168147,145656436074, 1685157199175,19886174611045,238819338399054, 2913166800256664,36036122671902718, 451429953643336590,5720172601392931006] |