n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 4 |
3 | 11 |
4 | 30 |
5 | 83 |
6 | 236 |
7 | 687 |
8 | 2026 |
9 | 6023 |
10 | 17984 |
11 | 53819 |
12 | 161254 |
13 | 483451 |
14 | 1449876 |
15 | 4348903 |
16 | 13045602 |
17 | 39135119 |
18 | 117402792 |
19 | 352204467 |
20 | 1056607454 |
[0,1,4,11,30,83,236,687,2026,6023,17984,53819, 161254,483451,1449876,4348903,13045602,39135119, 117402792,352204467,1056607454] |