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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 2 |
| 9 | 1 |
| 10 | 1 |
| 11 | 0 |
| 12 | 7 |
| 13 | 5 |
| 14 | 16 |
| 15 | 14 |
| 16 | 40 |
| 17 | 41 |
| 18 | 120 |
| 19 | 131 |
| 20 | 321 |
| 21 | 402 |
| 22 | 901 |
| 23 | 1210 |
| 24 | 2590 |
| 25 | 3621 |
| 26 | 7371 |
| 27 | 10841 |
| 28 | 21178 |
| 29 | 32222 |
| 30 | 61273 |
| 31 | 95408 |
| 32 | 177384 |
| 33 | 282405 |
| 34 | 515174 |
| 35 | 833295 |
| 36 | 1500030 |
| 37 | 2455337 |
| 38 | 4372535 |
| 39 | 7229231 |
| 40 | 12761691 |
| 41 | 21260746 |
| 42 | 37286778 |
| 43 | 62483221 |
| 44 | 109014426 |
| 45 | 183542099 |
| 46 | 318906720 |
| 47 | 538889399 |
| 48 | 933361886 |
| 49 | 1581666042 |
[0,1,0,0,0,0,0,2,1,1,0,7,5,16,14,40,41,120,131, 321,402,901,1210,2590,3621,7371,10841,21178,32222, 61273,95408,177384,282405,515174,833295,1500030, 2455337,4372535,7229231,12761691,21260746, 37286778,62483221,109014426,183542099,318906720, 538889399,933361886,1581666042] |