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| n | a(n) |
|---|---|
| 1 | 84 |
| 2 | 446 |
| 3 | 1770 |
| 4 | 9130 |
| 5 | 38332 |
| 6 | 192442 |
| 7 | 836546 |
| 8 | 4112126 |
| 9 | 18298862 |
| 10 | 88585834 |
| 11 | 400512170 |
| 12 | 1918066656 |
| 13 | 8765618868 |
| 14 | 41663142968 |
| 15 | 191790556024 |
| 16 | 906821509892 |
| 17 | 4194988138126 |
| 18 | 19763051033382 |
| 19 | 91728816380528 |
| 20 | 431069210118044 |
[84,446,1770,9130,38332,192442,836546,4112126, 18298862,88585834,400512170,1918066656,8765618868, 41663142968,191790556024,906821509892, 4194988138126,19763051033382,91728816380528, 431069210118044] |