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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 2 |
| 5 | 6 |
| 6 | 12 |
| 7 | 20 |
| 8 | 36 |
| 9 | 78 |
| 10 | 182 |
| 11 | 408 |
| 12 | 866 |
| 13 | 1802 |
| 14 | 3804 |
| 15 | 8208 |
| 16 | 17874 |
| 17 | 38802 |
| 18 | 83778 |
| 19 | 180660 |
| 20 | 390636 |
| 21 | 847490 |
| 22 | 1841868 |
| 23 | 4004124 |
| 24 | 8704740 |
| 25 | 18932398 |
| 26 | 41213490 |
| 27 | 89798064 |
| 28 | 195789922 |
| 29 | 427093530 |
| 30 | 932052968 |
| 31 | 2034966160 |
| 32 | 4445125152 |
| 33 | 9714318306 |
| 34 | 21238410158 |
| 35 | 46451025612 |
| 36 | 101630144708 |
[1,0,0,0,2,6,12,20,36,78,182,408,866,1802,3804, 8208,17874,38802,83778,180660,390636,847490, 1841868,4004124,8704740,18932398,41213490, 89798064,195789922,427093530,932052968,2034966160, 4445125152,9714318306,21238410158,46451025612, 101630144708] |