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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 17 |
| 6 | 69 |
| 7 | 310 |
| 8 | 1530 |
| 9 | 8079 |
| 10 | 45325 |
| 11 | 268362 |
| 12 | 1667358 |
| 13 | 10831443 |
| 14 | 73328952 |
| 15 | 515991884 |
| 16 | 3765585347 |
| 17 | 28445023673 |
| 18 | 222041323198 |
| 19 | 1788408340413 |
| 20 | 14842961368603 |
| 21 | 126784166379119 |
| 22 | 1113305431684358 |
| 23 | 10039694886817421 |
| 24 | 92889877402814064 |
| 25 | 880990917219289747 |
| 26 | 8557926084570679399 |
| 27 | 85078805258416836197 |
| 28 | 864992386976470929447 |
| 29 | 8987570189084296089971 |
| 30 | 95373920468324819686521 |
[1,1,1,2,5,17,69,310,1530,8079,45325,268362, 1667358,10831443,73328952,515991884,3765585347, 28445023673,222041323198,1788408340413, 14842961368603,126784166379119,1113305431684358, 10039694886817421,92889877402814064, 880990917219289747,8557926084570679399, 85078805258416836197,864992386976470929447, 8987570189084296089971,95373920468324819686521] |