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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 73 |
| 6 | 238 |
| 7 | 726 |
| 8 | 2101 |
| 9 | 5857 |
| 10 | 15926 |
| 11 | 42626 |
| 12 | 112997 |
| 13 | 297861 |
| 14 | 782666 |
| 15 | 2052958 |
| 16 | 5379953 |
| 17 | 14091781 |
| 18 | 36901646 |
| 19 | 96621062 |
| 20 | 252971401 |
| 21 | 662305301 |
| 22 | 1733959342 |
| 23 | 4539590666 |
| 24 | 11884834161 |
| 25 | 31114937393 |
| 26 | 81460008218 |
| 27 | 213265122686 |
| 28 | 558335401141 |
| 29 | 1461741128617 |
| 30 | 3826888039926 |
| 31 | 10018923054526 |
| 32 | 26229881196037 |
[1,1,2,6,21,73,238,726,2101,5857,15926,42626, 112997,297861,782666,2052958,5379953,14091781, 36901646,96621062,252971401,662305301,1733959342, 4539590666,11884834161,31114937393,81460008218, 213265122686,558335401141,1461741128617, 3826888039926,10018923054526,26229881196037] |