n | a(n) |
---|---|
1 | 0 |
2 | 2 |
3 | 9 |
4 | 54 |
5 | 300 |
6 | 1296 |
7 | 6300 |
8 | 39312 |
9 | 262440 |
10 | 1679616 |
11 | 10349856 |
12 | 62355744 |
13 | 369476640 |
14 | 2179768320 |
15 | 12958657344 |
16 | 77751944064 |
17 | 468419708160 |
18 | 2821109907456 |
19 | 16957996040448 |
20 | 101753146100736 |
21 | 609954817881600 |
22 | 3656158440062976 |
23 | 21926115464435712 |
24 | 131557435432187904 |
[0,2,9,54,300,1296,6300,39312,262440,1679616, 10349856,62355744,369476640,2179768320, 12958657344,77751944064,468419708160, 2821109907456,16957996040448,101753146100736, 609954817881600,3656158440062976, 21926115464435712,131557435432187904] |