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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 10 |
| 3 | 60 |
| 4 | 168 |
| 5 | 953 |
| 6 | 5304 |
| 7 | 29481 |
| 8 | 168320 |
| 9 | 990468 |
| 10 | 5920658 |
| 11 | 36118925 |
| 12 | 223452736 |
| 13 | 1398014617 |
| 14 | 8822174770 |
| 15 | 56061936636 |
| 16 | 358120024848 |
| 17 | 2296837339689 |
| 18 | 14776222949736 |
| 19 | 95279221861053 |
| 20 | 615439624491192 |
| 21 | 3980504657629172 |
[5,10,60,168,953,5304,29481,168320,990468,5920658, 36118925,223452736,1398014617,8822174770, 56061936636,358120024848,2296837339689, 14776222949736,95279221861053,615439624491192, 3980504657629172] |