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| n | a(n) |
|---|---|
| 4 | 1 |
| 5 | 11 |
| 6 | 79 |
| 7 | 471 |
| 8 | 2535 |
| 9 | 12809 |
| 10 | 62067 |
| 11 | 292085 |
| 12 | 1345718 |
| 13 | 6102780 |
| 14 | 27343148 |
| 15 | 121359692 |
| 16 | 534632836 |
| 17 | 2341151646 |
| 18 | 10201950700 |
| 19 | 44278673806 |
| 20 | 191540714294 |
| 21 | 826265471868 |
| 22 | 3555992623850 |
| 23 | 15273547250820 |
| 24 | 65491352071266 |
| 25 | 280412963707416 |
[1,11,79,471,2535,12809,62067,292085,1345718, 6102780,27343148,121359692,534632836,2341151646, 10201950700,44278673806,191540714294,826265471868, 3555992623850,15273547250820,65491352071266, 280412963707416] |