n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 1 |
4 | 0 |
5 | 2 |
6 | 5 |
7 | 14 |
8 | 42 |
9 | 122 |
10 | 360 |
11 | 1068 |
12 | 3181 |
13 | 9526 |
14 | 28654 |
15 | 86558 |
16 | 262528 |
17 | 799212 |
18 | 2441538 |
19 | 7483052 |
20 | 23004500 |
21 | 70921492 |
22 | 219226064 |
23 | 679328952 |
24 | 2109948221 |
25 | 6567539814 |
26 | 20483936790 |
27 | 64010196918 |
28 | 200382350016 |
29 | 628344541644 |
30 | 1973428795542 |
[1,1,1,0,2,5,14,42,122,360,1068,3181,9526,28654, 86558,262528,799212,2441538,7483052,23004500, 70921492,219226064,679328952,2109948221, 6567539814,20483936790,64010196918,200382350016, 628344541644,1973428795542] |