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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 81 |
| 3 | 221 |
| 4 | 663 |
| 5 | 2245 |
| 6 | 6459 |
| 7 | 17563 |
| 8 | 48649 |
| 9 | 131269 |
| 10 | 344873 |
| 11 | 902075 |
| 12 | 2342619 |
| 13 | 6021103 |
| 14 | 15395621 |
| 15 | 39219821 |
| 16 | 99470227 |
| 17 | 251449497 |
| 18 | 634148313 |
| 19 | 1595707571 |
| 20 | 4007571389 |
| 21 | 10049914241 |
| 22 | 25169768531 |
| 23 | 62965428327 |
| 24 | 157368593823 |
| 25 | 392995561393 |
[9,81,221,663,2245,6459,17563,48649,131269,344873, 902075,2342619,6021103,15395621,39219821,99470227, 251449497,634148313,1595707571,4007571389, 10049914241,25169768531,62965428327,157368593823, 392995561393] |