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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 256 |
| 3 | 912 |
| 4 | 3358 |
| 5 | 11196 |
| 6 | 38160 |
| 7 | 135714 |
| 8 | 471374 |
| 9 | 1605156 |
| 10 | 5575548 |
| 11 | 19518498 |
| 12 | 67332320 |
| 13 | 231918056 |
| 14 | 806844660 |
| 15 | 2802896674 |
| 16 | 9676886468 |
| 17 | 33492050252 |
| 18 | 116319708822 |
| 19 | 402977537782 |
| 20 | 1393754905624 |
| 21 | 4830422996784 |
| 22 | 16750871779658 |
[16,256,912,3358,11196,38160,135714,471374, 1605156,5575548,19518498,67332320,231918056, 806844660,2802896674,9676886468,33492050252, 116319708822,402977537782,1393754905624, 4830422996784,16750871779658] |