n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 3 |
4 | 18 |
5 | 60 |
6 | 214 |
7 | 1008 |
8 | 5280 |
9 | 29160 |
10 | 165840 |
11 | 940896 |
12 | 5196096 |
13 | 28304640 |
14 | 155270016 |
15 | 863910489 |
16 | 4861712448 |
17 | 27554100480 |
18 | 156728297088 |
19 | 892662156288 |
20 | 5088174124950 |
21 | 29045467518171 |
22 | 166186204664832 |
23 | 953309368018944 |
24 | 5481559804635648 |
25 | 31581437286776820 |
[0,0,3,18,60,214,1008,5280,29160,165840,940896, 5196096,28304640,155270016,863910489,4861712448, 27554100480,156728297088,892662156288, 5088174124950,29045467518171,166186204664832, 953309368018944,5481559804635648, 31581437286776820] |