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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 11 |
| 6 | 27 |
| 7 | 83 |
| 8 | 255 |
| 9 | 847 |
| 10 | 2829 |
| 11 | 9734 |
| 12 | 33724 |
| 13 | 118245 |
| 14 | 416816 |
| 15 | 1478602 |
| 16 | 5267171 |
| 17 | 18840144 |
| 18 | 67611472 |
| 19 | 243378415 |
| 20 | 878407170 |
| 21 | 3178068821 |
| 22 | 11523323634 |
| 23 | 41865833602 |
| 24 | 152382134767 |
[1,1,2,4,11,27,83,255,847,2829,9734,33724,118245, 416816,1478602,5267171,18840144,67611472, 243378415,878407170,3178068821,11523323634, 41865833602,152382134767] |