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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 4 |
| 7 | 9 |
| 8 | 11 |
| 9 | 26 |
| 10 | 23 |
| 11 | 55 |
| 12 | 64 |
| 13 | 154 |
| 14 | 134 |
| 15 | 323 |
| 16 | 373 |
| 17 | 900 |
| 18 | 781 |
| 19 | 1885 |
| 20 | 2174 |
| 21 | 5248 |
| 22 | 4552 |
| 23 | 10989 |
| 24 | 12671 |
| 25 | 30590 |
| 26 | 26531 |
| 27 | 64051 |
| 28 | 73852 |
| 29 | 178294 |
| 30 | 154634 |
| 31 | 373319 |
| 32 | 430441 |
| 33 | 1039176 |
| 34 | 901273 |
| 35 | 2175865 |
| 36 | 2508794 |
| 37 | 6056764 |
| 38 | 5253004 |
| 39 | 12681873 |
| 40 | 14622323 |
| 41 | 35301410 |
[1,0,1,1,2,4,4,9,11,26,23,55,64,154,134,323,373, 900,781,1885,2174,5248,4552,10989,12671,30590, 26531,64051,73852,178294,154634,373319,430441, 1039176,901273,2175865,2508794,6056764,5253004, 12681873,14622323,35301410] |