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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 27 |
| 5 | 61 |
| 6 | 809 |
| 7 | 13945 |
| 8 | 268027 |
| 9 | 565447 |
| 10 | 2358365 |
| 11 | 73551683 |
| 12 | 2734683311 |
| 13 | 112599773191 |
| 14 | 4860900544813 |
| 15 | 9968041656757 |
| 16 | 40762420985117 |
| 17 | 83151858555707 |
| 18 | 5085105491885327 |
| 19 | 341472595155548909 |
| 20 | 24295409051193284539 |
[1,2,11,27,61,809,13945,268027,565447,2358365, 73551683,2734683311,112599773191,4860900544813, 9968041656757,40762420985117,83151858555707, 5085105491885327,341472595155548909, 24295409051193284539] |