# A280889 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 75
4 56
5 6930
6 28512
7 2849847
8 972400
9 693870606
10 99936200
11 63488350926
12 475814969280
13 166184959669300
14 497980728000
15 78877488833249175
16 1489333512849120
17 1116126129558913110
18 1597083864660900000
19 4467282986266589095530
20 107279471180408841600