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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 177 |
| 5 | 823 |
| 6 | 3953 |
| 7 | 19003 |
| 8 | 92593 |
| 9 | 451880 |
| 10 | 2220395 |
| 11 | 10923924 |
| 12 | 53945354 |
| 13 | 266670612 |
| 14 | 1321190761 |
| 15 | 6550924502 |
| 16 | 32527305279 |
| 17 | 161609300887 |
| 18 | 803687085750 |
| 19 | 3998717143782 |
| 20 | 19908167842642 |
| 21 | 99153850510870 |
| 22 | 494066742281765 |
| 23 | 2462601445739490 |
| 24 | 12278579512463422 |
| 25 | 61236110775014294 |
| 26 | 305475906740399446 |
[1,2,9,38,177,823,3953,19003,92593,451880,2220395, 10923924,53945354,266670612,1321190761,6550924502, 32527305279,161609300887,803687085750, 3998717143782,19908167842642,99153850510870, 494066742281765,2462601445739490, 12278579512463422,61236110775014294, 305475906740399446] |