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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 9 |
| 3 | 41 |
| 4 | 202 |
| 5 | 938 |
| 6 | 4354 |
| 7 | 20330 |
| 8 | 94625 |
| 9 | 439959 |
| 10 | 2045048 |
| 11 | 9500746 |
| 12 | 44124084 |
| 13 | 204883131 |
| 14 | 951202028 |
| 15 | 4415710979 |
| 16 | 20497646229 |
| 17 | 95146359635 |
[2,9,41,202,938,4354,20330,94625,439959,2045048, 9500746,44124084,204883131,951202028,4415710979, 20497646229,95146359635] |