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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 32 |
| 4 | 139 |
| 5 | 618 |
| 6 | 2815 |
| 7 | 13017 |
| 8 | 60855 |
| 9 | 287001 |
| 10 | 1362415 |
| 11 | 6502201 |
| 12 | 31167650 |
| 13 | 149934312 |
| 14 | 723476714 |
| 15 | 3499963998 |
| 16 | 16969632025 |
| 17 | 82436773668 |
| 18 | 401150765071 |
| 19 | 1955002514510 |
| 20 | 9540432897408 |
| 21 | 46613349333715 |
| 22 | 227993425528368 |
| 23 | 1116247039256627 |
| 24 | 5469986043680742 |
| 25 | 26826680102548173 |
| 26 | 131665972445904744 |
[1,2,8,32,139,618,2815,13017,60855,287001,1362415, 6502201,31167650,149934312,723476714,3499963998, 16969632025,82436773668,401150765071, 1955002514510,9540432897408,46613349333715, 227993425528368,1116247039256627,5469986043680742, 26826680102548173,131665972445904744] |