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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 23 |
| 2 | 67 |
| 3 | 197 |
| 4 | 581 |
| 5 | 1717 |
| 6 | 5081 |
| 7 | 15051 |
| 8 | 44619 |
| 9 | 132357 |
| 10 | 392825 |
| 11 | 1166383 |
| 12 | 3464543 |
| 13 | 10294187 |
| 14 | 30595831 |
| 15 | 90958325 |
| 16 | 270471141 |
| 17 | 804429189 |
| 18 | 2392956009 |
| 19 | 7119580287 |
| 20 | 21185591199 |
| 21 | 63050397375 |
| 22 | 187668462027 |
| 23 | 558658899825 |
| 24 | 1663222335825 |
[1,23,67,197,581,1717,5081,15051,44619,132357, 392825,1166383,3464543,10294187,30595831,90958325, 270471141,804429189,2392956009,7119580287, 21185591199,63050397375,187668462027,558658899825, 1663222335825] |