n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 9 |
4 | 48 |
5 | 180 |
6 | 972 |
7 | 7056 |
8 | 48384 |
9 | 297432 |
10 | 1762560 |
11 | 10349856 |
12 | 60466176 |
13 | 356638464 |
14 | 2139830784 |
15 | 12958657344 |
16 | 78399995904 |
17 | 472093588224 |
18 | 2832129868032 |
19 | 16960580969472 |
20 | 101565116448768 |
21 | 608764662139392 |
22 | 3652526115938304 |
23 | 21926115464435712 |
24 | 131621703842267136 |
[0,0,9,48,180,972,7056,48384,297432,1762560, 10349856,60466176,356638464,2139830784, 12958657344,78399995904,472093588224, 2832129868032,16960580969472,101565116448768, 608764662139392,3652526115938304, 21926115464435712,131621703842267136] |