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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 10 |
| 6 | 23 |
| 7 | 52 |
| 8 | 120 |
| 9 | 275 |
| 10 | 644 |
| 11 | 1508 |
| 12 | 3558 |
| 13 | 8418 |
| 14 | 20012 |
| 15 | 47699 |
| 16 | 114082 |
| 17 | 273476 |
| 18 | 657250 |
| 19 | 1582817 |
| 20 | 3819514 |
| 21 | 9233059 |
| 22 | 22356918 |
| 23 | 54216429 |
| 24 | 131663670 |
| 25 | 320158789 |
| 26 | 779461271 |
| 27 | 1899830067 |
| 28 | 4635492672 |
| 29 | 11321595218 |
| 30 | 27677333555 |
| 31 | 67720658475 |
| 32 | 165835173692 |
[0,0,1,2,5,10,23,52,120,275,644,1508,3558,8418, 20012,47699,114082,273476,657250,1582817,3819514, 9233059,22356918,54216429,131663670,320158789, 779461271,1899830067,4635492672,11321595218, 27677333555,67720658475,165835173692] |