n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 0 |
3 | 1 |
4 | 3 |
5 | 8 |
6 | 20 |
7 | 53 |
8 | 137 |
9 | 375 |
10 | 1035 |
11 | 2878 |
12 | 7988 |
13 | 22308 |
14 | 62642 |
15 | 176692 |
16 | 499818 |
17 | 1418228 |
18 | 4035568 |
19 | 11512449 |
20 | 32916181 |
21 | 94313011 |
22 | 270757747 |
23 | 778694171 |
24 | 2243200705 |
25 | 6471953522 |
26 | 18699169766 |
27 | 54098598824 |
28 | 156706773404 |
29 | 454457344755 |
30 | 1319382151919 |
31 | 3834346819731 |
[0,0,0,1,3,8,20,53,137,375,1035,2878,7988,22308, 62642,176692,499818,1418228,4035568,11512449, 32916181,94313011,270757747,778694171,2243200705, 6471953522,18699169766,54098598824,156706773404, 454457344755,1319382151919,3834346819731] |