n | a(n) |
---|---|
1 | 0 |
2 | 6 |
3 | 40 |
4 | 122 |
5 | 488 |
6 | 1608 |
7 | 5392 |
8 | 17368 |
9 | 55232 |
10 | 172896 |
11 | 535296 |
12 | 1641376 |
13 | 4992896 |
14 | 15083648 |
15 | 45297408 |
16 | 135323008 |
17 | 402405376 |
18 | 1191699968 |
19 | 3516119040 |
20 | 10339711488 |
21 | 30313351168 |
22 | 88624646144 |
23 | 258445856768 |
24 | 751910639616 |
25 | 2182836600832 |
[0,6,40,122,488,1608,5392,17368,55232,172896, 535296,1641376,4992896,15083648,45297408, 135323008,402405376,1191699968,3516119040, 10339711488,30313351168,88624646144,258445856768, 751910639616,2182836600832] |