n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 1 |
3 | 0 |
4 | 3 |
5 | 0 |
6 | 15 |
7 | 1 |
8 | 105 |
9 | 36 |
10 | 945 |
11 | 990 |
12 | 10396 |
13 | 25740 |
14 | 136942 |
15 | 675675 |
16 | 2238405 |
17 | 18378361 |
18 | 50490765 |
19 | 523833819 |
20 | 1665638325 |
21 | 15790609395 |
22 | 71976549646 |
23 | 515107015830 |
24 | 3524757498023 |
25 | 19222751356875 |
26 | 181500385651325 |
27 | 888496839591076 |
28 | 9603885700913400 |
[1,0,1,0,3,0,15,1,105,36,945,990,10396,25740, 136942,675675,2238405,18378361,50490765,523833819, 1665638325,15790609395,71976549646,515107015830, 3524757498023,19222751356875,181500385651325, 888496839591076,9603885700913400] |