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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 33 |
| 7 | 128 |
| 8 | 109 |
| 9 | 344 |
| 10 | 3760 |
| 11 | 1829 |
| 12 | 18367 |
| 13 | 11168 |
| 14 | 35246 |
| 15 | 41103 |
| 16 | 79356 |
| 17 | 151643 |
| 18 | 344725 |
| 19 | 1249071 |
| 20 | 1678788 |
| 21 | 5385320 |
| 22 | 19780986 |
| 23 | 17348076 |
| 24 | 30966961 |
| 25 | 85647848 |
| 26 | 160394455 |
| 27 | 451333739 |
| 28 | 623813606 |
[1,1,2,4,8,33,128,109,344,3760,1829,18367,11168, 35246,41103,79356,151643,344725,1249071,1678788, 5385320,19780986,17348076,30966961,85647848, 160394455,451333739,623813606] |