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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 9 |
| 7 | 20 |
| 8 | 42 |
| 9 | 87 |
| 10 | 189 |
| 11 | 419 |
| 12 | 926 |
| 13 | 2080 |
| 14 | 4724 |
| 15 | 10783 |
| 16 | 24785 |
| 17 | 57374 |
| 18 | 133454 |
| 19 | 311882 |
| 20 | 732084 |
| 21 | 1725019 |
| 22 | 4078661 |
| 23 | 9674563 |
| 24 | 23014591 |
| 25 | 54894296 |
| 26 | 131254246 |
| 27 | 314544591 |
| 28 | 755369735 |
| 29 | 1817530413 |
| 30 | 4381176005 |
| 31 | 10578753769 |
| 32 | 25583847608 |
| 33 | 61964393295 |
| 34 | 150288117481 |
[0,1,1,1,3,5,9,20,42,87,189,419,926,2080,4724, 10783,24785,57374,133454,311882,732084,1725019, 4078661,9674563,23014591,54894296,131254246, 314544591,755369735,1817530413,4381176005, 10578753769,25583847608,61964393295,150288117481] |