n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 4 |
4 | 18 |
5 | 144 |
6 | 1200 |
7 | 14400 |
8 | 176400 |
9 | 2822400 |
10 | 45722880 |
11 | 914457600 |
12 | 18441561600 |
13 | 442597478400 |
14 | 10685567692800 |
15 | 299195895398400 |
16 | 8414884558080000 |
17 | 269276305858560000 |
18 | 8646761377013760000 |
19 | 311283409572495360000 |
[1,1,4,18,144,1200,14400,176400,2822400,45722880, 914457600,18441561600,442597478400,10685567692800, 299195895398400,8414884558080000, 269276305858560000,8646761377013760000, 311283409572495360000] |