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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 28 |
| 4 | 88 |
| 5 | 256 |
| 6 | 704 |
| 7 | 1856 |
| 8 | 4736 |
| 9 | 11776 |
| 10 | 28672 |
| 11 | 68608 |
| 12 | 161792 |
| 13 | 376832 |
| 14 | 868352 |
| 15 | 1982464 |
| 16 | 4489216 |
| 17 | 10092544 |
| 18 | 22544384 |
| 19 | 50069504 |
| 20 | 110624768 |
| 21 | 243269632 |
| 22 | 532676608 |
| 23 | 1161822208 |
| 24 | 2524971008 |
| 25 | 5469372416 |
| 26 | 11811160064 |
| 27 | 25434259456 |
[1,2,8,28,88,256,704,1856,4736,11776,28672,68608, 161792,376832,868352,1982464,4489216,10092544, 22544384,50069504,110624768,243269632,532676608, 1161822208,2524971008,5469372416,11811160064, 25434259456] |