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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 1 |
| 6 | 6 |
| 7 | 6 |
| 8 | 21 |
| 9 | 30 |
| 10 | 82 |
| 11 | 141 |
| 12 | 342 |
| 13 | 650 |
| 14 | 1485 |
| 15 | 2982 |
| 16 | 6612 |
| 17 | 13693 |
| 18 | 29922 |
| 19 | 63072 |
| 20 | 136905 |
| 21 | 291618 |
| 22 | 631302 |
| 23 | 1353441 |
| 24 | 2928054 |
| 25 | 6303798 |
| 26 | 13642117 |
| 27 | 29454702 |
| 28 | 63791456 |
| 29 | 138020533 |
| 30 | 299191968 |
| 31 | 648376932 |
| 32 | 1406836717 |
| 33 | 3052671816 |
| 34 | 6629649798 |
| 35 | 14400972413 |
| 36 | 31301837952 |
[1,0,2,1,6,6,21,30,82,141,342,650,1485,2982,6612, 13693,29922,63072,136905,291618,631302,1353441, 2928054,6303798,13642117,29454702,63791456, 138020533,299191968,648376932,1406836717, 3052671816,6629649798,14400972413,31301837952] |