n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 1 |
3 | 6 |
4 | 30 |
5 | 160 |
6 | 975 |
7 | 6846 |
8 | 54796 |
9 | 493200 |
10 | 4932045 |
11 | 54252550 |
12 | 651030666 |
13 | 8463398736 |
14 | 118487582395 |
15 | 1777313736030 |
16 | 28437019776600 |
17 | 483429336202336 |
18 | 8701728051642201 |
19 | 165332832981201990 |
20 | 3306656659624039990 |
21 | 69439789852104840000 |
[0,0,1,6,30,160,975,6846,54796,493200,4932045, 54252550,651030666,8463398736,118487582395, 1777313736030,28437019776600,483429336202336, 8701728051642201,165332832981201990, 3306656659624039990,69439789852104840000] |