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| n | a(n) |
|---|---|
| 1 | 47 |
| 2 | 173 |
| 3 | 735 |
| 4 | 3192 |
| 5 | 13917 |
| 6 | 60779 |
| 7 | 265605 |
| 8 | 1161035 |
| 9 | 5075841 |
| 10 | 22191959 |
| 11 | 97027389 |
| 12 | 424226867 |
| 13 | 1854830841 |
| 14 | 8109825551 |
| 15 | 35458405365 |
| 16 | 155034056747 |
| 17 | 677852377137 |
| 18 | 2963761021319 |
| 19 | 12958396425645 |
| 20 | 56657753602595 |
| 21 | 247723635757161 |
[47,173,735,3192,13917,60779,265605,1161035, 5075841,22191959,97027389,424226867,1854830841, 8109825551,35458405365,155034056747,677852377137, 2963761021319,12958396425645,56657753602595, 247723635757161] |