n | a(n) |
---|---|
0 | 0 |
1 | 3 |
2 | 6 |
3 | 12 |
4 | 30 |
5 | 78 |
6 | 222 |
7 | 636 |
8 | 1878 |
9 | 5556 |
10 | 16590 |
11 | 49548 |
12 | 148422 |
13 | 444630 |
14 | 1333254 |
15 | 3997884 |
16 | 11991774 |
17 | 35969766 |
18 | 107903742 |
19 | 323694636 |
20 | 971067318 |
21 | 2913152406 |
22 | 8739407670 |
23 | 26218074588 |
24 | 78654075342 |
25 | 235961781396 |
26 | 707884899558 |
27 | 2123653365420 |
28 | 6370958763006 |
[0,3,6,12,30,78,222,636,1878,5556,16590,49548, 148422,444630,1333254,3997884,11991774,35969766, 107903742,323694636,971067318,2913152406, 8739407670,26218074588,78654075342,235961781396, 707884899558,2123653365420,6370958763006] |