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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 3 |
| 6 | 5 |
| 7 | 24 |
| 8 | 60 |
| 9 | 102 |
| 10 | 258 |
| 11 | 816 |
| 12 | 1992 |
| 13 | 4452 |
| 14 | 12012 |
| 15 | 33617 |
| 16 | 84627 |
| 17 | 212823 |
| 18 | 577361 |
| 19 | 1561077 |
| 20 | 4063059 |
| 21 | 10715009 |
| 22 | 29052015 |
| 23 | 78235107 |
| 24 | 208358693 |
| 25 | 560561391 |
| 26 | 1522609569 |
| 27 | 4120277283 |
| 28 | 11129752269 |
| 29 | 30240233739 |
| 30 | 82441619605 |
| 31 | 224488878600 |
| 32 | 611770878012 |
[1,0,0,1,3,3,5,24,60,102,258,816,1992,4452,12012, 33617,84627,212823,577361,1561077,4063059, 10715009,29052015,78235107,208358693,560561391, 1522609569,4120277283,11129752269,30240233739, 82441619605,224488878600,611770878012] |