n | a(n) |
---|---|
0 | 1 |
1 | 3 |
2 | 9 |
3 | 24 |
4 | 66 |
5 | 180 |
6 | 486 |
7 | 1314 |
8 | 3558 |
9 | 9606 |
10 | 25956 |
11 | 70134 |
12 | 189462 |
13 | 511866 |
14 | 1382880 |
15 | 3735888 |
16 | 10092762 |
17 | 27266340 |
18 | 73661610 |
19 | 199001490 |
20 | 537615066 |
21 | 1452399978 |
22 | 3923748270 |
[1,3,9,24,66,180,486,1314,3558,9606,25956,70134, 189462,511866,1382880,3735888,10092762,27266340, 73661610,199001490,537615066,1452399978, 3923748270] |