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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 2 |
| 8 | 2 |
| 9 | 4 |
| 10 | 11 |
| 11 | 16 |
| 12 | 43 |
| 13 | 87 |
| 14 | 123 |
| 15 | 250 |
| 16 | 736 |
| 17 | 2189 |
| 18 | 3152 |
| 19 | 9501 |
| 20 | 19909 |
| 21 | 28861 |
| 22 | 88250 |
| 23 | 186540 |
| 24 | 575703 |
| 25 | 2605063 |
| 26 | 5556059 |
| 27 | 8118935 |
| 28 | 17356074 |
| 29 | 25389718 |
| 30 | 54388168 |
| 31 | 789812633 |
| 32 | 1700415401 |
| 33 | 5380882786 |
| 34 | 7903301746 |
| 35 | 54185536387 |
| 36 | 79678647536 |
| 37 | 253610377475 |
[0,1,0,1,1,1,2,2,4,11,16,43,87,123,250,736,2189, 3152,9501,19909,28861,88250,186540,575703,2605063, 5556059,8118935,17356074,25389718,54388168, 789812633,1700415401,5380882786,7903301746, 54185536387,79678647536,253610377475] |