n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 1 |
3 | 3 |
4 | 10 |
5 | 15 |
6 | 45 |
7 | 120 |
8 | 351 |
9 | 528 |
10 | 1540 |
11 | 4095 |
12 | 11935 |
13 | 17955 |
14 | 52326 |
15 | 139128 |
16 | 405450 |
17 | 609960 |
18 | 1777555 |
19 | 4726275 |
20 | 13773376 |
21 | 20720703 |
22 | 60384555 |
23 | 160554240 |
24 | 467889345 |
25 | 703893960 |
26 | 2051297326 |
27 | 5454117903 |
28 | 15894464365 |
29 | 23911673955 |
30 | 69683724540 |
31 | 185279454480 |
[0,0,1,3,10,15,45,120,351,528,1540,4095,11935, 17955,52326,139128,405450,609960,1777555,4726275, 13773376,20720703,60384555,160554240,467889345, 703893960,2051297326,5454117903,15894464365, 23911673955,69683724540,185279454480] |