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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 9 |
| 6 | 13 |
| 7 | 35 |
| 8 | 63 |
| 9 | 1587 |
| 10 | 3733 |
| 11 | 130673 |
| 12 | 393655 |
| 13 | 13792523 |
| 14 | 50382037 |
| 15 | 6128617283 |
| 16 | 28568095487 |
| 17 | 6379895824947 |
| 18 | 37360214342889 |
| 19 | 13793098704317291 |
| 20 | 100685778534490077 |
| 21 | 83983096306346152831 |
| 22 | 769168839966983823023 |
[1,1,1,1,9,13,35,63,1587,3733,130673,393655, 13792523,50382037,6128617283,28568095487, 6379895824947,37360214342889,13793098704317291, 100685778534490077,83983096306346152831, 769168839966983823023] |