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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 126 |
| 3 | 1978 |
| 4 | 32703 |
| 5 | 556887 |
| 6 | 9665476 |
| 7 | 170006256 |
| 8 | 3019802253 |
| 9 | 54047520709 |
| 10 | 973141183002 |
| 11 | 17607177876438 |
| 12 | 319855973830251 |
| 13 | 5830329608105763 |
| 14 | 106583422441886592 |
| 15 | 1953315343946213804 |
| 16 | 35875864591309216089 |
| 17 | 660185366847433991025 |
| 18 | 12169379986275311820790 |
[1,9,126,1978,32703,556887,9665476,170006256, 3019802253,54047520709,973141183002, 17607177876438,319855973830251,5830329608105763, 106583422441886592,1953315343946213804, 35875864591309216089,660185366847433991025, 12169379986275311820790] |