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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 6 |
| 7 | 24 |
| 8 | 79 |
| 9 | 233 |
| 10 | 640 |
| 11 | 1674 |
| 12 | 4224 |
| 13 | 10370 |
| 14 | 24912 |
| 15 | 58800 |
| 16 | 136767 |
| 17 | 314201 |
| 18 | 714209 |
| 19 | 1608604 |
| 20 | 3594007 |
| 21 | 7973108 |
| 22 | 17576844 |
| 23 | 38531060 |
| 24 | 84040238 |
| 25 | 182467033 |
| 26 | 394537387 |
| 27 | 849885436 |
| 28 | 1824495630 |
| 29 | 3904453264 |
| 30 | 8331493468 |
| 31 | 17730810536 |
| 32 | 37641301271 |
| 33 | 79727649682 |
| 34 | 168512283733 |
[0,0,0,0,1,6,24,79,233,640,1674,4224,10370,24912, 58800,136767,314201,714209,1608604,3594007, 7973108,17576844,38531060,84040238,182467033, 394537387,849885436,1824495630,3904453264, 8331493468,17730810536,37641301271,79727649682, 168512283733] |