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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1716 |
| 3 | 54573 |
| 4 | 492724 |
| 5 | 2467137 |
| 6 | 8786436 |
| 7 | 25066621 |
| 8 | 61189668 |
| 9 | 133071009 |
| 10 | 264735892 |
| 11 | 490704621 |
| 12 | 858686676 |
| 13 | 1432583713 |
| 14 | 2295801444 |
| 15 | 3554870397 |
| 16 | 5343375556 |
| 17 | 7826194881 |
| 18 | 11204046708 |
| 19 | 15718346029 |
| 20 | 21656369652 |
| 21 | 29356730241 |
| 22 | 39215159236 |
| 23 | 51690598653 |
| 24 | 67311601764 |
[0,1,1716,54573,492724,2467137,8786436,25066621, 61189668,133071009,264735892,490704621,858686676, 1432583713,2295801444,3554870397,5343375556, 7826194881,11204046708,15718346029,21656369652, 29356730241,39215159236,51690598653,67311601764] |