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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 41 |
| 5 | 153 |
| 6 | 573 |
| 7 | 2157 |
| 8 | 8163 |
| 9 | 31043 |
| 10 | 118559 |
| 11 | 454479 |
| 12 | 1747771 |
| 13 | 6740059 |
| 14 | 26055459 |
| 15 | 100939779 |
| 16 | 391785129 |
| 17 | 1523230569 |
| 18 | 5931153429 |
| 19 | 23126146629 |
| 20 | 90282147849 |
| 21 | 352846964649 |
| 22 | 1380430179489 |
| 23 | 5405662979649 |
| 24 | 21186405207549 |
| 25 | 83101804279101 |
| 26 | 326199124351701 |
[1,1,3,11,41,153,573,2157,8163,31043,118559, 454479,1747771,6740059,26055459,100939779, 391785129,1523230569,5931153429,23126146629, 90282147849,352846964649,1380430179489, 5405662979649,21186405207549,83101804279101, 326199124351701] |