n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 3 |
3 | 9 |
4 | 33 |
5 | 99 |
6 | 315 |
7 | 945 |
8 | 2883 |
9 | 8649 |
10 | 26091 |
11 | 78273 |
12 | 235233 |
13 | 705699 |
14 | 2118339 |
15 | 6355017 |
16 | 19068729 |
17 | 57206187 |
18 | 171629595 |
19 | 514888785 |
20 | 1544699313 |
21 | 4634097939 |
22 | 13902392691 |
23 | 41707178073 |
24 | 125121830427 |
25 | 375365491281 |
[0,0,3,9,33,99,315,945,2883,8649,26091,78273, 235233,705699,2118339,6355017,19068729,57206187, 171629595,514888785,1544699313,4634097939, 13902392691,41707178073,125121830427,375365491281] |