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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 21 |
| 3 | 69 |
| 4 | 177 |
| 5 | 964 |
| 6 | 3249 |
| 7 | 13801 |
| 8 | 56505 |
| 9 | 228913 |
| 10 | 905649 |
| 11 | 3647572 |
| 12 | 14560636 |
| 13 | 58313644 |
| 14 | 233143837 |
| 15 | 932944592 |
[1,5,21,69,177,964,3249,13801,56505,228913,905649, 3647572,14560636,58313644,233143837,932944592] |