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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 175 |
| 5 | 808 |
| 6 | 3849 |
| 7 | 18383 |
| 8 | 88999 |
| 9 | 431862 |
| 10 | 2110755 |
| 11 | 10334433 |
| 12 | 50809851 |
| 13 | 250155363 |
| 14 | 1234791555 |
| 15 | 6101767949 |
| 16 | 30203112734 |
| 17 | 149633428158 |
| 18 | 742180468673 |
| 19 | 3683782579592 |
| 20 | 18299486557614 |
| 21 | 90954995144055 |
| 22 | 452356538672065 |
| 23 | 2250765627720072 |
| 24 | 11204242622439625 |
| 25 | 55794642239484282 |
| 26 | 277945913282431755 |
[1,2,9,38,175,808,3849,18383,88999,431862,2110755, 10334433,50809851,250155363,1234791555,6101767949, 30203112734,149633428158,742180468673, 3683782579592,18299486557614,90954995144055, 452356538672065,2250765627720072, 11204242622439625,55794642239484282, 277945913282431755] |