n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 7 |
3 | 23 |
4 | 72 |
5 | 204 |
6 | 564 |
7 | 1521 |
8 | 4059 |
9 | 10747 |
10 | 28336 |
11 | 74504 |
12 | 195576 |
13 | 512865 |
14 | 1344063 |
15 | 3521007 |
16 | 9221688 |
17 | 24148468 |
18 | 63230860 |
19 | 165555665 |
20 | 433454835 |
21 | 1134839091 |
22 | 2971111392 |
23 | 7778574288 |
24 | 20364739632 |
25 | 53315851969 |
26 | 139583151799 |
27 | 365434146311 |
28 | 956720165544 |
[0,1,7,23,72,204,564,1521,4059,10747,28336,74504, 195576,512865,1344063,3521007,9221688,24148468, 63230860,165555665,433454835,1134839091, 2971111392,7778574288,20364739632,53315851969, 139583151799,365434146311,956720165544] |