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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 9 |
| 5 | 37 |
| 6 | 319 |
| 7 | 743 |
| 8 | 2509 |
| 9 | 2761 |
| 10 | 32891 |
| 11 | 35201 |
| 12 | 485333 |
| 13 | 511073 |
| 14 | 535097 |
| 15 | 1115239 |
| 16 | 19679783 |
| 17 | 6786821 |
| 18 | 133033679 |
| 19 | 136913555 |
| 20 | 140608675 |
| 21 | 144135835 |
| 22 | 678544345 |
| 23 | 693417203 |
| 24 | 17692378667 |
| 25 | 18035598467 |
| 26 | 165294957803 |
| 27 | 168163294703 |
[0,0,1,9,37,319,743,2509,2761,32891,35201,485333, 511073,535097,1115239,19679783,6786821,133033679, 136913555,140608675,144135835,678544345,693417203, 17692378667,18035598467,165294957803,168163294703] |