n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 1 |
4 | 15 |
5 | 222 |
6 | 3660 |
7 | 68295 |
8 | 1436568 |
9 | 33779340 |
10 | 880107840 |
11 | 25201854045 |
12 | 787368574080 |
13 | 26667815195274 |
14 | 973672928417280 |
15 | 38132879409281475 |
16 | 1594927540549217280 |
17 | 70964911709203684440 |
18 | 3347306760024413356032 |
19 | 166855112441313024389625 |
20 | 8765006377126199463936000 |
[0,0,1,15,222,3660,68295,1436568,33779340, 880107840,25201854045,787368574080,26667815195274, 973672928417280,38132879409281475, 1594927540549217280,70964911709203684440, 3347306760024413356032,166855112441313024389625, 8765006377126199463936000] |