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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 10 |
| 5 | 24 |
| 6 | 50 |
| 7 | 108 |
| 8 | 220 |
| 9 | 452 |
| 10 | 916 |
| 11 | 1860 |
| 12 | 3744 |
| 13 | 7560 |
| 14 | 15202 |
| 15 | 30576 |
| 16 | 61420 |
| 17 | 123360 |
| 18 | 247542 |
| 19 | 496692 |
| 20 | 996088 |
| 21 | 1997272 |
| 22 | 4003558 |
| 23 | 8023884 |
| 24 | 16077964 |
| 25 | 32212248 |
| 26 | 64527436 |
| 27 | 129246660 |
| 28 | 258847876 |
| 29 | 518358120 |
| 30 | 1037949256 |
| 31 | 2078209980 |
| 32 | 4160747500 |
| 33 | 8329633416 |
| 34 | 16674575056 |
| 35 | 33378031536 |
[0,0,1,4,10,24,50,108,220,452,916,1860,3744,7560, 15202,30576,61420,123360,247542,496692,996088, 1997272,4003558,8023884,16077964,32212248, 64527436,129246660,258847876,518358120,1037949256, 2078209980,4160747500,8329633416,16674575056, 33378031536] |