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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 9 |
| 6 | 17 |
| 7 | 47 |
| 8 | 169 |
| 9 | 947 |
| 10 | 4301 |
| 11 | 28001 |
| 12 | 189379 |
| 13 | 2123749 |
| 14 | 21459731 |
| 15 | 367346875 |
| 16 | 5385601539 |
[1,1,1,1,9,17,47,169,947,4301,28001,189379, 2123749,21459731,367346875,5385601539] |