n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 6 |
4 | 24 |
5 | 90 |
6 | 306 |
7 | 1008 |
8 | 3240 |
9 | 10266 |
10 | 32190 |
11 | 100188 |
12 | 310074 |
13 | 955500 |
14 | 2934288 |
15 | 8986086 |
16 | 27456840 |
17 | 83735370 |
18 | 254962062 |
19 | 775270908 |
20 | 2354646294 |
21 | 7144301016 |
22 | 21657653028 |
23 | 65603494458 |
24 | 198584527338 |
25 | 600758100540 |
26 | 1816426149876 |
27 | 5489387016378 |
28 | 16582071393240 |
[0,0,6,24,90,306,1008,3240,10266,32190,100188, 310074,955500,2934288,8986086,27456840,83735370, 254962062,775270908,2354646294,7144301016, 21657653028,65603494458,198584527338,600758100540, 1816426149876,5489387016378,16582071393240] |