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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 5 |
| 6 | 20 |
| 7 | 35 |
| 8 | 102 |
| 9 | 217 |
| 10 | 540 |
| 11 | 1160 |
| 12 | 2634 |
| 13 | 5467 |
| 14 | 11463 |
| 15 | 22786 |
| 16 | 44848 |
| 17 | 85068 |
| 18 | 159018 |
| 19 | 288914 |
| 20 | 516643 |
| 21 | 903256 |
| 22 | 1554696 |
| 23 | 2626217 |
| 24 | 4372347 |
| 25 | 7163317 |
| 26 | 11580760 |
| 27 | 18462388 |
| 28 | 29078307 |
| 29 | 45236642 |
| 30 | 69602057 |
| 31 | 105917976 |
| 32 | 159571937 |
| 33 | 238035458 |
| 34 | 351841043 |
| 35 | 515413775 |
| 36 | 748727920 |
[1,0,1,1,4,5,20,35,102,217,540,1160,2634,5467, 11463,22786,44848,85068,159018,288914,516643, 903256,1554696,2626217,4372347,7163317,11580760, 18462388,29078307,45236642,69602057,105917976, 159571937,238035458,351841043,515413775,748727920] |